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KODAK LIMITED • WEALDSTONE • HARROW • MIDDLESEX PUBLIC UTILITIES IN RECONSTRUCTION NATURE HE eleventh report of the Select Committee on T National Expenditure gives fresh pertinence to the discussion in the House of Lords on the extent, No. 3803 SATURDAY, SEPT. 19, 1942 Vol. 150 control and management of the essential public services, which Lord Reith initiated, and Mr. Bevin’s speech to the National Chamber of Trade on July 15 CONTENTS Page also raised these important questions as to the exact Public Utilities in Reconstruction .... 329 relations between Government and industry and the Physics in Biology. By Dr. Harold Jeffreys, F.R.S. 332 nature and extent of State intervention. Whatever Measurement of Trees. By E. P. S. . 333 concern may be felt as to the capacity of the Civil Social Geography in India. By Prof. H. J. Fleure, F.R.S. 334 Service in this respect, no report that has fairly faced A Problem in Econometrics. By Dr. A. L. Bowley, the issues involved in reconstruction fails to recognize C.B.E., F.B.A...... 335 that some large measure of intervention will be Catalysed Polymerization of Methyl Methacrylate in the Liquid Phase. By Prof. R. G. W. Norrish, F.R.S., necessary for a prolonged period after the War. That and R. R. Smith ...... 336 follows at once from the recognition that the Govern­ Illumination and Visual Range under Water. By Dr. ment must assume responsibility for creating the H. H. P o o l e ...... 337 social and economic conditions in which our objectives The Figure of the Earth. By Dr. R. Stoneley, F.R.S. . 339 of economic security, steady employment, greater Obituaries : equality of opportunity and distribution and a rising Prof. F. E. Suess. By J. V. Harrison . .341 standard of living can be secured. Mr. E. A. Nahum. By Prof. J. D. Bernal, F.R.S. . 341 From the point of view of the relations between the News and Views ...... 342 State and industry, Government has two functions. Letters to the Editors : The first, which is negative, is to act as referee Raman Spectrum of I, 3, 5-Triphenyl Benzene.— Prof. S. K. Mukerji and Laksman Singh . 347 between the various economic groups, to secure and Formation of a Double Crystal Aggregate and the maintain economic freedom and remove the present Structure of the Intermediate Temperature institutional defects—the tendency towards combina­ Modification of Ni (N 0 3)2.6NH3.— S. H.Yü . 347 tions in restraint of trade, the resistance to adaptation Mechanism of Metallic Friction.— Dr. J. E. Hurst . 349 to new circumstances which nearly always develops Shape of Subjective Space.— Shaun M. Cox . 349 from monopolistic practices, and the power of Role of Adenine Nucleotides and Growth Factors managers of industry to make decisions which may in Increased Proliferation following Damage to Cells.— Prof. John R. Loofbourow . 349 vitally and even adversely affect the interests of the Sexuality in Dugesio tigrina (syn. Planaria maculata). community without being accountable to the com­ — Dr. E. D. Goldsmith ..... 351 munity. This function probably involves revision of The Public Schools in Great Britain.— Prof. J. D. the patent laws. It certainly involves constant Bernal, F.R.S.; Prof. P. G. H. Boswell, O.B.E., vigilance and control over monopolistic practices, a F.R.S.; Prof. S. Brodetsky; Prof. J. Chadwick, new code of industrial behaviour, some modification F.R.S.; Prof. W. E. Le Gros Clark, F.R.S.; Brig.- General F. A. E. Crew, F.R.S.; Prof. C. Lovatt of the Companies Act, and more publicity from Evans, F.R.S.; Prof. B. Farrington; Prof. C. B. companies about their activities. Fawcett; Prof. Sargant Florence; Prof. P. F. The second function of Government is positive and Frankland, C.B.E., F.R.S.; Prof. Lancelot Hogben, directive. It is that of ensuring that the whole com­ F.R.S.; Prof. Julian Huxley, F.R.S.; Dr. R. K. Kelsall; Prof. R. D. Laurie; Dr. Joseph Needham, munity is properly fed, clothed and housed, and F.R.S.; Prof. R. Pascal; Prof. J. A. Ryle; Dr. F. preventing the periodic recurrence of large-scale and Soddy, F.R.S.; Dr. H. G. Stead; Prof. Geo. demoralizing unemployment. In certain spheres it Thomson; Prof. F. E. Weiss, F.R.S.; Prof. F. may involve the subordination of the profit motive Wood-Jones, F.R.S...... 351 to social incentive, though there should remain a vast Research Items ...... 352 The League of Nations ...... 354 area of industry and trade in which the fullest pos­ Man-power in the National Fire Service . 354 sible scope is given to enterprise and profit as the Contact Resistance ...... 355 mainsprings of efficiency, adaptability and enterprise. Magnetic Fluxmeter ...... 355The main problem is that of harmonizing the interests of the economic groups and those of the community, of reconciling freedom and security without losing the Editorial and Publishing Offices driving force of enterprise. M A CM ILLAN & CO., LTD., It is when we enter on the discussion of the evolu­ ST. MARTIN’S STREET, LONDON, W.C.2 tion of the suitable technique of control that the Telephone Number: Whitehall 8831 main difficulties arise. No single formula is suitable Telegrams : Phusis Lesquare London for all purposes and for all forms of economic activity Advertisements should be addressed to which it is desirable to control or supervise. Some T. G. Scott & Son, Ltd., Talbot House, 9, Arundel Street, London, W.C.2 Telephone : Temple Bar 1942-3 activities or industries might be taken over entirely The annual subscription rate is £4 10 0, payable in advance, Inland o r Abroad by Government. In this category fall certain public All rights* reserved. Registered as a Newspaper at the General Post Office services and industries that have reached an advanced stage of development. For this the Post Office or the from getting full value from the key men. Indi­ public corporation might serve as the model, and it vidualism is still required. Key men must be trusted, was to this aspect that Lord Reith directed special and governors and managers permitted to exercise attention in his speech in the House of Lords on their natural functions of governing and managing June 17. Stressing the importance of giving the the corporations they serve, and to which and for ideal of public service precedence over other factors which they are responsible. A planned society such as political considerations and the profit motive, should be a free society, and it should and must be he emphasized the importance of efficient and dis­ planned for freedom. interested administration and appeared to advocate It is because the tradition of the Civil Service, with a considerable extension of the public utility corpora­ its caution, love of precedence and the Treasury tion. He suggested a National Transport Corpora­ methods of control with their emphasis on higher tion covering railways, road transport, canals, coast­ authority rather than on efficiency, does not encourage wise shipping and internal air services, and urged initiative or even a proper sense of responsibility in that the railways should be brought under unified departments, that whatever form or technique is used management and become part of the Corporation. for extending the measure of Government control, the In some measure central regulation and control are day-to-day operation of the services and industries required in the building and civil engineering and concerned should be entrusted to competent managers building materials industries, both to settle prices and rather than to Civil servants. Lord Reith indeed to secure economy in materials and machines, stan­ suggested that Civil servants should not be concerned dardization, and the adoption of codes of practice with the management of essential public services, and and research. that the postal services, including telegraphs, tele­ Lord Reith would amalgamate the Central Elec­ phones and wireless services, though now highly tricity Board and the Electricity Commissioners, with efficient, would be notably more so if they were not a the object of securing a uniform price for electricity Government department subject to Government over the whole of Great Britain. Gas and water, methods of financial accounting and control, and that roads and river management, sewage and subsoil the same remark might apply to such other services water are other services in which there are too many as pensions and insurance. authorities and too many types of authority. While The realization of this inherent weakness in the the duties and responsibilities of the public corpora­ Civil servant lies behind the discussion which recently tion system would be defined by the State in charter took place regarding the headship of the Civil Service, and statute, and Parliament would be consulted on and reflects the criticism of Treasury methods of policy, Lord Reith would give them the same freedom control and outlook contained in the Haldane report in organization and management as in commercial on the Machinery of Government, and discussed last undertakings. year in a P E P broadsheet. The nature and extent of the public services to pass An illustration of the incapacity of a Government under Government control may be the subject of department in management matters is provided by debate. Lord Strabolgi was somewhat critical of the report of the Select Committee already men­ Lord Reith’s suggestions. He agreed that it is tioned. This inquiry into the working of the royal essential that our plans should be made known and ordnance factories reveals clear signs of failure to accepted, and that we should plan for peace as we plan with sufficient attention to securing a proper should have planned for war. So far as transport is balance between the various parts. For example, in concerned, his emphasis was laid on overseas trans­ regard to filling capacity and the capacity for the port, and civil aviation must also be included. He manufacture of components, although at one factory believes that all external transport should come 57 per cent of the floor space is at present lying idle, under some measure of State control. Viscount no record of the total amount of unused capacity is Bledisloe also agreed that there must be very con­ kept at the headquarters of the Ministry of Supply, siderable control of transport and even in agricultural and the Department was unable to make more than production for many years after the War ; that, he a rough guess at the total amount in all factories. said, need not imply or justify State ownership, and Indeed, it was not considered the Department’s he stressed the importance of getting away from the business to know. Similarly, the redundancy of party point of view and of being prepared to make labour in factories affords evidence of failure to sacrifices in our political outlook in order to obtain exercise sufficient forethought and to adapt actual something like national unity and co-operative arrangements to probable future developments. The effort. discrepancies in the estimates of redundancy which In spite of these differences of opinion as to the exist between the headquarters officials and those services to be controlled, there is widespread agree­ actually in charge of factories indicate another aspect ment as to the importance of leadership and of finding of faulty organization. The division of responsi­ the men to carry the great responsibilities involved. bility for royal ordnance factories, and the confused Lord Strabolgi believes that the new aristocracy of dispersal of responsibility for matters affecting the leaders required will emerge from the War in young handling of labour tell the same tale of failure to men and women who can be trusted to put public recognize the importance of a clear appreciation of interest before the profit motive, and to manage these the proper functions of the various parts of the organ­ great undertakings efficiently. Lord Reith, however, ization. thinks that our lack of institutions has prevented us What is particularly disturbing is that the importance of matters of organization was specially due to insufficient regard for local information and stressed in the Select Committee’s Seventh and Eighth for the desires of the workers, or like the failure to deal Reports, which emphasized the necessity of replacing seriously with the problems of absenteeism, or the hasty improvisation by carefully balanced plans replacement of men by women, is primarily a reflec­ which ensure the best possible use of the limited tion on management, and as such demands prompt resources of Great Britain. The need for the clear action by the Minister of Production. The country is planning of programmes based on an accurate appre­ fast becoming impatient of a state of affairs in which ciation of existing factors and probable future continued neglect of informed, responsible and con­ developments was specially stressed. These warnings, structive criticism of the type which characterizes like many of the habitual tools and techniques of these reports of the Select Committee is possible. modem industrial management, have been sadly This report undoubtedly adds great weight to that disregarded in general and in detail. important volume of opinion voiced by Lord Reith, as On the organization side, neither at headquarters well as, for example, by Mr. Samuel Courtauld in his nor at the factory has the machinery been provided article in the Economic Journal (Reprint, Macmillan to integrate the responsibility for the various specialist and Co., Ltd. “Government and Industry : Their functions and services. In the factories, effective F utu re Relations” , 1942, 6d. net), which is against control by the superintendent has been hampered by direct Government control of industry, though the the encroachment of specialist authorities, a tendency necessity for control is admitted. Whatever method encouraged also by the regional administration of of control is adopted—and there are other methods to filling factories. Functional control has been carried be explored as well as that of the public corporation— too far, and the recommendation for placing the it is essential that there shall be full control over the control of all types of royal ordnance factories under controllers on behalf of the community and to ensure one director-general is accompanied by the further efficiency. It may be sufficient in some particular recommendation for the transfer to him of all labour services or industries to exercise control over general questions inherent in the management of the factories policy, with free play for private enterprise and the or administered by separate authorities. The deputy - profit motive. Again, some essential services might be director-general responsible for labour should not deliberately subsidized to make necessities available merely have full access to all relevant information, at a low price ; or again, we might explore the possi­ but should also be brought into consultation at bility of nationalizing the costly equipment of certain every stage in all matters involving major questions industries, leaving their management in the hands of of policy. He should not be concerned with those private enterprise. matters of labour supply, such as recruiting, which Whatever method be adopted, there is no reason are the proper concern of the Ministry of Labour. why Parliamentary control or criticism should be Of the twenty-four recommendations of this report, excluded, particularly on questions of policy, and any there is not one which would not be endorsed or attempt to screen the public corporation from such adopted by industrial management as a matter of control would be unwise. Equally, it is certain that course, and some of them indicate a startling contrast the separation of day-to-day control of public services between the practice and outlook of the Ministry and or industry from the Civil Service should not render that of industry. The accumulation of stocks of the reform of the Civil Service less imperative or materials and components to secure a proper flow afford any pretext for shelving the attempt to bring of supplies ; attention by the designing staffs to ease a new outlook, greater flexibility and modern tech­ and economy in producing the completed product, nique into the Service, while retaining the great and full testing from the production point of view of traditions and great qualities which have justly won every design before acceptance ; the application of it the respect and admiration of the world. statistical methods of control of manufacture to all On this point Mr. G. D. H. Cole has an interesting suitable items of production ; time and motion contribution in a recent issue of Public Administration studies and the introduction of incentive bonus (20, 1 ; 1942). Writing on reconstruction in the schemes ; uniformity of methods and standards of civil and municipal services, he considers that neither inspection for the various products and factories ; the national nor the local public services are likely to and the regular exchange of visits and of records and revert to their pre-war methods and traditions. The other documentary information between the super­ war-time changes have left too deep a mark, and intendents of royal ordnance factories and the large changes are desirable in view of the changing managers of private firms engaged on similar work— functions of national and local government and of these, to take only a few points, are so much the the need for extensive readjustments in the very accustomed practice in industry that it is astonishing structure of the machinery of government. that a Select Committee should find it necessary to Mr. Cole limits himself mainly to the personnel side, make recommendations on such specific practices. and urges that we must consider afresh the qualities The significance of these details lies in the revela­ we chiefly require in the public services of the future, tion they give of the extent to which the Civil Service and the methods of training, recruitment, promotion has fallen behind industry in its use and knowledge and movement within them which are most likely to of organization and scientific management. Insuffi­ bring these qualities to the fore. This involves, of cient liaison between design and production depart­ course, some consideration of the relation between ments, for example, like the strictures in the report the public services and other types of professional passed on the errors in siting and designing hostels employment, and particularly the relation between conditions in the semi-public services or public utility PHYSICS IN BIOLOGY concerns and those in the public services or in private business. The twelfth report of the Select Committee On Growth and Form on National Expenditure, although dealing particu­ By Sir D’Arcy Wentworth Thompson. Revised and larly with two appointments in the Ministry of Works enlarged edition. Pp. viii f- 11 16. (Cam bridge: At and Buildings, certainly raises doubts as to the the U niversity Press, 1942.) 50s. net. soundness of the present practice. The conditions T may seem sufficiently obvious that living tissue laid down by the Treasury to facilitate the appoint­ is to a large extent subject to physical and chemical ment of able men who are expert in a special sphere lawsI ; if a man falls off a cliff he is as much subject are obviously open to abuse, and the dangers in wide to gravity as a stone is, and the action of nitric acid disparity in the remuneration of the same type of or excessive heat on skin is much the same whether work and ability by the State and in private industry the skin is alive or dead. Sir D’Arcy Thompson’s should need no further emphasis. well-known work, now in its second edition, gives The reform of the public services in this way is not many illustrations that are less obvious. The author finds that at all stages of growth the mode and rate exclusively a matter for those who control these of formation of new tissue are largely determined by services ; it also concerns those whose task it is to the form of the organism at the time ; and since this shape the educational system in conformity with in turn determines the rate and distribution of growth, changing social needs. Thus Mr. Cole concludes that, the development is reducible to differential equations next to plain honesty, the quality which the Civil with regard to the time. Service will be called upon most to display in the work It would be impossible to give a summary of a book of reconstruction is adaptability. This is just the that is itself a summary, indicating prodigious quality in which it is most lacking to-day. To remedy learning. A few examples may, however, be given. it, Mr. Cole suggests a greater diversity of experience, There is a very promising attempt to reduce nuclear division to physical processes : the explanation of the greater direct acquaintance with the things and forms of the septas of Nautilus and of cell-walls in persons affected for good or ill by the decisions of terms of surface tension looks complete. The forma­ Civil servants, and a wider basis both for recruitment tion of buds is attributed to a local concentration of at varying ages and for promotion to the key positions potassium salts, which reduce the surface tension of authority. He looks forward to a drastic over­ locally, and the surface is pushed out farther by hauling of the municipal services, leading to much internal pressure. The increased curvature increases higher standards of recruitment and possibly to the local adsorption of potassium and we have an frequent interchange between the service of the local instability leading to a bud. But what determines authority and the service of the State, thus enabling the spacing of buds on the stem ? Apparently, for less than a certain interval, the budless stem is stable, Civil servants in the departments affected to have and it is not easy to see why. Such difficulties periods of service away from the centre. A further should lead to further investigation, and the atten­ advantage would be the gradual disappearance of the tion of mathematical physicists might be directed to unfortunate sharp demarcation between the national them. Fortunately, the author’s language is not of and municipal Civil services. the type common in biological writing, where about Besides welcoming some disturbance of the excessive one noun in three may convey any meaning to a non­ security and tranquility of the Civil Service, Mr. Cole specialist. He does, however, sometimes use a maintains that the administrative qualities required physical term in a non-physical sense. For example, for the highest offices are not to be found only among in discussing nuclear division he speaks of the impor­ tance of inertia (p. 309). On this scale inertia, as a the higher non-technical administrators from whose physicist understands it, must be negligible in com­ ranks they are usually filled ; he anticipates a large parison with viscosity ; and I cannot see what other new infusion into both services of technical and profes­ meaning is intended. “Vector” is used in an unusual sional elements, and the breaking down of the lines of physical sense on p. 78. demarcation between these elements and the ordinary It is a pity that in the discussion of energy rela­ administrative grades. This should be a natural result tions in propulsion no reference is made to the fact of the demand for the services of widely diverse types that the square law of resistance only holds above a of specialists in reconstruction, as well as for the certain velocity depending on the size ; below this permanent expansion of the social services. velocity a linear law holds, and may be the right one for small organisms. It is not true, as stated on Measures such as these, which have been frequently p. 31, that in an unstreamlined body the drag increases advocated during the last decade, should do some­ as the cube of the velocity ; it is nearly as the square, thing to bring a more democratic, imaginative and but with a larger coefficient than for a streamlined adventurous spirit into the Civil Service than in the body. On p. 43 it is stated that birds and aeroplanes past. They inevitably involve some disturbance of are helped to fly by the compressibility of the air ; the severely cloistered life which many Civil servants this is not so, compressibility being practically are accustomed to enjoy, and if at the same time irrelevant so long as the velocity is less than that of there is exercised the power of compulsory retirement sound. With regard to the normal law of errors where a Civil servant has shown himself unfit for his (p. 124), a correct statem ent would be th a t deviations equal to the standard error divide the area of the post, a matter on which Mr. Cole, like the P E P curve nearly in the ratios 1:4:1 and coincide broadsheet, lays great emphasis, there should be less exactly with the inflexions. In the allusion to the difficulty in instilling and maintaining initiative and advantage of a long narrow wing in birds, explicit efficiency in a service which has deservedly earned for reference to the reduction of induced drag would be itself a world-wide reputation. beneficial. An experiment is mentioned on p. 565 as providing a strong argument that general shrinkage and never happened on Venus. In any event, does not account for the pattern of the earth’s crust. though anybody making a living organism in the This is surprising, because the irrelevance of the laboratory would probably get a Nobel Prize, we experiment was pointed out at once in the same are warned against suggesting it as a problem to a journal; it was a case of elastic instability, which is Ph.D. student. easily produced on a laboratory or workshop scale, It is superfluous to recommend the book to biolog­ but not in the earth’s crust as a whole. A rhumb-line ists, who will know enough about the first edition ; on a sphere is not a great circle (p. 675). to them the reviewer need only say that abundant I t appears th a t the opinions propounded in the book attention has been given to later work. But mathe­ have been regarded as antagonistic to natural selec­ matical and experimental physicists will find in it, at tion and that the author acquiesces in that opinion. the least, extremely interesting reading, and some of I do not see why. Surely it is possible that the more them, one may hope, suggestions that will repay an organism can leave the physical and chemical further research. H arold Jeffreys. processes to look after themselves, the better adapted it is to its environment. A machine is considered better the less frequently it needs special attention, and the same may be true of an organism. Mother Carey’s “I can make things make themselves” may MEASUREMENT OF TREES be the remark of a profound biologist. Also, if life Measurement of Trees is most efficient when most of its processes can be By Reginald Davey. Pp. 236. (Nutley, Sussex : left to physics and chemistry, the difficulty of finding The Forest Press, 1942.) 21s. direct evidence for a specific ‘life force’ is explained on a vitalist theory and ceases to be an argument N his book, Mr. R. Davey tells us that the work is against it. the outcome of three years research into I think that most of this controversy arises from a BritishI commercial methods. “It is”, he says, “the failure to state the question properly. I quote from first systematic study of the ocular system of measur­ pp. 14-15. “Where physical science reaches its ing growing trees.” His laudable object was a limitations physical science itself must help us to simplification of methods of measuring trees and discover. Meanwhile, the appropriate and legitimate woods for sale, “so that the exercise of care can postulate of the physicist, in approaching the physical secure results at present attainable only after years problems of the living body, is that with these physical of practice”. One of the chief objects of the research phenomena no alien influence interferes. But the work was the much-vexed question of ‘taper’ in the postulate, though it is certainly legitimate, and though bole. it is the proper and necessary prelude to scientific Officers of the Forestry Commission have under­ inquiry, may some day be proven to be untrue ; and taken a considerable amount of investigation into its disproof will not be to the physicist’s confusion, this matter in the case of conifers. With regard to but will come as his reward.” But what is discussed hardwoods, there should be no quarrel with the in this passage is not a postulate a t all, b ut a considered author’s work, statistical tables, and views, if it is proposition. If we assert that no alien influence understood clearly that they are drawn up for present interferes, we assert that this statement will never conditions and existing woods in Great Britain, where be proved untrue, and there is no occasion to discuss true forest management and sylviculture, with few what will happen if it is. If we assert that some exceptions, have been admittedly absent. Con­ other influence does interfere, and make use of the sequently, as a general rule, the boles of the trees statement that none does, we contradict ourselves at in a wood develop a taper which it is the object of every turn. It is precisely because we neither assert good sylvicultural treatment to reduce to a minimum. nor deny the proposition that there is any need to Nature, in the natural forests of the world, as a investigate. But a postulate must be an asserted result of considerable profusion and waste and long proposition. A considered proposition, however, is periods of time, produces the final product in a bole simply one possible answer to a question, in this case resembling more and more the cylinder, between the that physics can account for all the phenomena. The base of the stem and the point at which the main scientific urge comes from considered propositions branches take off. This is a common sight in the and is hindered, if not destroyed, if they are pre­ tropical forest. The same is observable in the con­ maturely asserted. The paradoxical conclusion of iferous belt in northern Europe. Moreover, in the the above quotation is, in fact, the result of a verbal case of some of the well-managed oak and beech confusion, which is none the less dangerous for being forests in France, worked on rotations of 180-200 a common one. years, the bole, that is, the merchantable timber part •Further, I have followed the distinguished author in of the tree in which the author is interested, is far assuming that we do know what we mean by “living”. nearer the cylinder than the cone or paraboloid, and does But do we ? We may agree that a flying swallow is not resemble the diagrams in his Fig. 1. Moreover, living and that a stone is not ; but have we any the buttress or ‘root-swelling’ in the case of these empirical criterion that we can apply in every latter is restricted and has little resemblance to the instance ? Without one the proposition enunciated author’s neiloid—so much so that the French prac­ is not even intelligible. tice is to dig a small trench and expose the basal Again, Sir D ’Arcy says (p. 650) th a t it does not help parts of the root system and fell the tree by severing us to say that molecular asymmetry may have orig­ the roots near their junction with the stem. inated in fortuity. But there is a close enough In a book based on research work which should resemblance between the earth and Venus for us to have a considerable value in Great Britain it appears suppose that life could have developed on Venus ; that the above points should be placed in their proper and recent work makes us confident that it has not perspective, a perspective which emphasizes perhaps done so. I think that it does help us to say that an the value for Britain of the work, in view of remarks extremely rare event happened once on the earth such as the following. Mr. Davey writes : “Trees rarely resemble either cone, paraboloid or neiloid for unthriftiness in land-use, fright and ill-treatment in their whole length.” If by ‘whole length’ the author the hands of money-lender and landlord, and wide implies timber length to the main branching, even dominance of superstitions that the rationalizing pro­ in the case of conifers it is evident that he has never cesses of urban life may later on too easily transform seen a great deodar (Cedrus deodara) standing in the into a subservience to mass emotion. forests of the north-west Himalaya. Again we read : Sometimes the author seems to continue the old “Owing to heavy branching there is less uniformity error of so many writers on social subjects in sup­ in the stems of hardwoods . . . the branches are posing that a nomadic pastoral stage of society inter­ seen to be larger in proportion to the stem, set on the vened between the earlier one of hunting and collect­ stem less evenly and generally to affect the shape of ing and the later one of food production by cultiva­ the stem for a greater part of the length.” While tion. All the indications we have, admittedly still in­ this description probably applies to 90 per cent or sufficient, go to show that from hunting, mainly by more of the hardwoods grown in Great Britain, it the men, and collecting, mainly by women and would not be accepted by anyone who has seen an children, society often graded to cultivation (by the old teak, s’al, deodar or mahogany tree in a fine piece women and later by the enslaved men of conquered of virgin forest, or oak in well-managed long rotation or client groups). Herding m ay have arisen in different forests in France. The book is well illustrated with ways in different cases, but seems more often to have plates and text-figures, and its get-up, in these days, developed as an accessory to cultivation rather than is a credit to publisher and printer. E. P. S. as a preliminary to it. The communities that depend almost entirely on flocks and herds are usually highly specialized ones, though cases are known in which they have become transformed, usually under ex­ SOCIAL GEOGRAPHY IN INDIA ternal pressure, into cultivators. If Mukerjee does Man and his Habitation tend to put pastoralism before cultivation sometimes, A Study in Social Ecology. Ey Prof. Radhakamal he, at any rate, sees it is associated with certain en­ Mukerjee. (Lucknow University Studies, No. 12.) vironments unfavourable to cultivation because of Pp. xv + 313. (London, New York and Toronto : upland positions, drought, etc. Longmans, Green and Co., Ltd., 1940.) 8s. 6d. net. He has a good deal to say concerning the boys’ dormitory, with sometimes another for the girls ; and HE relations of man and society are a prominent his section on the early evolution of habitation in subject of contemporary discussion. Traditional India in its relation to forest clearing by fire for T links everywhere are weakening and new experimentsshifting cultivation gives an interesting sequence that are to the fore. In many books we read discussions emphasizes the great and widespread importance of that, often unconsciously, presuppose a European or the aboriginal, if to some extent Hinduized, elements North American background ; but, in this case, the in Indian life. The village dormitory for boys, the background is Indian and the differences in facts houses of the advance guard, housing of a slightly adduced as well as in lines of argument make a reader better type for the headman and his kinship group wonder whether there is really such a subject as and in due course for the ceremonial leaders in process social science or whether there are not rather numerous of evolution towards a priesthood, as well as the ‘social geographies’ to be studied. menstruation hut are all reviewed. A place in a The author thinks that it is useful to study society, grove may become the centre of ceremony, but the in its relation with habitation, under three heads, temple may also arise from a house under which namely, density (of population, of dwellings, of burials have taken place and whence ancestral spirits groups, and so on) ; mobility (including mobility of may come into the women for rebirth. An unparti­ status as well as mobility of persons and of groups tioned communal hut may be an alternative, or even a and their habitations) ; and distance (including here still earlier, feature. There are people such as the contrasts of status as well as distance in the physical Kabuis in Manipur who hold on to one and the same sense). Density, mobility and distances are thus to village site and yet shift their area of cultivation be studied with special reference to their social and year by year in a set rotation. Houses come to be institutional implications. All through his book the arranged around a dancing floor, and separate quar­ author is specially concerned with the contrasted ters of the village are differentiated for diverse kin­ implications of urban and rural life, particularly in ship groups, with the unkempt hangers-on relegated India, but also in the United States and, to some to an outlying patch as untouchables. One may note extent, in Europe. for comparison the gipsy quarters appended to many Relatively high density, quick mobility and sharp east-central European villages and some of the social division or distance are considered to be features “little Londons” hanging on to small English towns. of urbanization under which human relations tend Mukerjee has much to say concerning the Panch- to become transitory, segmental and superficial, regu­ ayat, which, on the whole, he tends to idealize lated by more or less rationalized contractual arrange­ and wants to see revived in towns as well as ments ; whereas a lower density, a much slower villages. The Panchayat may bo an assembly of change and a closely graded hierarchy taking more elders of a village or a caste-group in a large village, account of personal skill and worth are, for him, and it has in the author’s opinion checked the alliance features of rural life. He nevertheless sees that there of urban and rural capitalism which he seems to fear is an up and down movement of caste groups, yet as an agreement between kites and crows at the ex­ not a sufficiently rapid change to upset the solidarity pense of sparrows. In some of his reflections on of the village. The thought behind this is essentially Europe there is a tendency to ascribe to capitalism that expressed by Sir Henry Maine in his view of the changes that have come largely through the use of gradation from status to contract and from kinship root crops. to. neighbourhood. While Mukerjee expatiates on the From different chapters one gets interesting hints evils of urbanism, he sees also the weak side of as to diversities between different provinces and Indian village life—the tenacious conservatism, the regions in India, and the whole book leaves one with a sense of the vitality of the Indian villages and a considered in Chapter 8. There is also a persistent wish that the author had given us a book on India 40-months cycle in stock exchange and allied series, and had foregone rather less profitable general socio­ for which no cause has been assigned. I t is a weakness logical surveys, though his knowledge of countries of harmonic analysis as applied to economic series, outside India compares more than favourably with the that it can reveal only waves of uniform length, knowledge of some noted European writers concern­ whereas the length of the trade cycle has perhaps ing peoples outside Europe. Mukerjee’s book is in­ varied from seven to eleven years during the past spired by the hope of a planned economy in which hundred years ; if the effect of a nine-year period is durability of relationship will once more increase, and removed, new and irregular residuals are introduced. intimate touch witli the land and personal loyalties Residuals. The effect of the removal of the trend shall have their chance. and cyclical movements is measured by the reduction H. J . F l e u r e . of the ‘variance’ of the series. Thus, if s is the original standard deviation, we may write A PROBLEM IN ECONOMETRICS s 2 = sf + s\ + s i where st,sh,sv are the standard deviations attributable The Analysis of Economic Time Series to the trend, the harmonics and the residuals re­ By Harold T. Davis. (Cowles Commission for Research spectively. The relative sizes of these squares are in Economics, Monograph No. 6.) Pp. xv + 620. taken as measuring the ‘energy’ of the three factors. (Bloomington, Ind. : The Principia Press, Inc. ; The residuals, though free from systematic move­ London : Williams and Norgate, Ltd., 1941.) 5 dollars. ments, may nevertheless have some structure; as for CONOMETRICS may be described as the applica­ example, an increase may be followed by a further E tion of mathematics to statistics for the elucida­ increase more often than by a decrease, and auto­ tion of economic forces and the measurement of their correlation (correlation between one term and a later effects. Since those actions are dynamic the principal term) may be present. The author devotes an in­ data are successive records in time, or time series, teresting chapter to the study of random series, and in recent years many mathematical economists with reference also to the possibility of forecasting have made them the subject of intensive study. Mr. movements when there is autocorrelation. But per­ Barold T. Davis has brought together and criticized haps the main importance of sv is as a measurement the theories and methods employed in this region, and of the magnitude of the variation that may be ex­ illustrated them with a wealth of new material. His pected from unassignable causes. The behaviour of a summary of his subject is (p. 59) : “The problem of series as regards trend, cycle and nature of the residual single time series is concerned with three things : is clearly an important subject of observation ; but first, the determination of a trend ; second, the dis­ study of the relationship between two or more series covery and interpretation of cyclical movements in is more fundamental for econometrics. For this pur­ the residuals ; third, the determination of the mag­ pose the correlation of the residuals, xt and yt+t, nitude of the erratic element in the data. This pre­ from two series is computed for various values of s, liminary problem, once solved, leads immediately into the number of terms lagged (s zero is itself important). the more complex one of discovering valid inter­ The usual process, followed by Mr. Davis, is to com­ actions of one time series with another. Upon the pute the correlation coefficient for several values of s, discovery of such relationships the hope of establish­ and select the maximum ; thus we have the following ing a firm science of economics inevitably rests. From coefficients between stock-market quotations (the them will come ultimately the power of prediction, Dow-Jones averages) and pig-iron production (s in which is the final test of any mature science.” months) The Trend. If there are causes of a permanent or organic nature that affect the whole series, we may expect that their effects can be expressed by mathe­ matical formula;, or by some smoothing process. Thus a straight line, parabola or polynomial, applied to the From this, Mr. Davis’s conclusion (p. 105) is : “This terms or their successive ratios, may give a general means that pig-iron production follows by three picture of the movement over a long period, and leave months the industrial averages”, and later (p. 235), residuals the algebraic averages of which over short this becomes, “It was established that pig-iron pro­ periods are zero. Continual growth, as of population duction moves three months after the stock price or production, may require an exponential expression, averages”. Surely this is too strong a statement; usually with a damping term ; that most used is the the correlation coefficient is only an average, only ‘logistic’, the equation of which is ~ x ) one of several possible averages ; a relationship is no doubt shown, but action based on it would by no In the author’s opinion such curves can be successful means always be successful. only if they are based on some a priori theory. Failing Space does not permit even allusion to all of the any successful choice of an equation, the alternative many topics discussed, or criticism of the less mathe­ is the device of the moving average, or some other matical chapters on wealth and other economic sub­ arithmetical method of smoothing. jects, which are less guarded than the purely analytical Cyclical movements. The mathematician naturally studies. Parts of the book are very difficult reading, turns to harmonic analysis to determine the existence and only possible to a qualified mathematician, who of, and to measure, regular periodic movements, and should be prepared to refer to the originals of studies Mr. Davis devotes a great deal of his book to the where results are only summarized. The whole is a nature and use of the periodogram and to the periods very valuable account of the work that has already indicated by it in a number of selected series. The been done in this important region, while at the same periods most generally found are seasonal, which time many indications are given of promising lines of require no logical explanation, and the ‘trade cycle’ approach towards the basing of some parts of economic for the genesis of which many ingenious theories are theory on a quantitative basis. A. L. B o w l e y . CATALYSED POLYMERIZATION OF of polymer, being the linear extrapolation to zero concentration of the expression : (spec, viscosity in METHYL METHACRYLATE IN THE acetone / conc. of polymer, base mols. per litre).

LIQUID PHASE T a b l e 1. P olymerization o f u n d il u t e d m e t h y l methacrylate . T e m p . 25° 0. 0-410 m o l . p e r c e n t B zaO ,. R a t e a p p r o x . s t e a d y UP TO 12 PER CENT POLYMERIZATION. By P rof- R. G. W. NORRISH, F.R.S., and R. R. SMITH Department of Physical Chemistry, Cambridge SING benzoyl peroxide as catalyst, Norrish and U Brookman1 found that the order of the poly­ merization reaction of undiluted methyl methacrylate is approximately zero in the first stages ; the initial rate of reaction is proportional to the square root of the catalyst concentration2. The rate of reaction was found to rise markedly after about 10-20 per cent polymerization, and at the same time considerable heating of the system took place. Norrish and In Table 2 the square root law is illustrated, and Brookman supposed that the temperature rise caused it can be seen that the rise in rate was found to occur the rate increase, the former arising from a decrease latest in the polymerization with the highest catalyst of thermal convection in the system with increasing concentration. viscosity during polymerization. After experiments T a b l e 2. P olymerization o f u n d il u t e d m e t h y l methacrylate on catalysed and uncatalysed reactions, Schulz and T e m p . 60° C. Blaschke3 took the opposite view, namely, that the rate increase mainly caused the temperature rise, and supposed that the former was due to an increase in the rate of initiation of active centres. In order to test these two views, we polymerized methyl methacrylate slowly in narrow glass tubes (4-5 mm. internal diameter) a t 60°, 40° and 25°C., using less than about 1 mol. per cent of benzoyl peroxide. The extent of reaction was measured dilatometrically up to about 40-50 per cent change. Under these Further, with the same catalyst concentration, we conditions, we found that the rate of polymeriza­ found that higher temperature also caused a later tion was nearly steady in the initial stages (up to rise. High catalyst and temperature are conditions 12-26 per cent polymerization, depending on the for producing a low bulk viscosity of the polymerizing temperature and catalyst concentration), yet after­ system for a given percentage reaction. This fact, wards quickened to about 5-10 times the earlier rate, together with our observations on the rise of chain- despite the fact that the maximum temperature in length throughout polymerization, suggested to us each tube rarely rose more than 1° C. from the that increasing bulk viscosity is indeed essentially thermostat reading in any of our experiments. It is responsible for the rise in rate and chain-length, in thus evident that much of the change in velocity is that it decreases the rate ‘constant’ of termination k 3. not due to temperature rise, but further observation For if k3 decreases throughout polymerization, the rate led us to question whether it was due to an increase and the chain-length will both rise. In this connexion in the rate of initiation of centres as suggested by Gee5 has referred to the possibility of ks decreasing Schulz and Blaschke. throughout polymerization. In view of analogies in the kinetics, it seems reason­ As a critical experiment we polymerized methyl able to accept for methyl methacrylate a theory of methacrylate at 40° G. with 0-0094 mol. Bza0 2 per polymerization similar to that substantiated by litre in the presence of a series of diluents (see Fig. 1) Schulz4 for styrene. Thus, if C is the catalyst con­ each 40 per cent by volume. The diluents were chosen centration, M the monomer concentration, and n the from good and poor solvents and also precipitants of concentration of active centres, the rate of initiation polymethyl methacrylate, so that the bulk viscosity of chains is given by k-fi, the rate of propagation by of each system at a given percentage polymerization l\n M , and the rate of termination by k 3n 2. This would differ as greatly as possible. In order to obtain gives the steady rate of polymerization as —dM jdt = a measure of the extent of this variation in bulk viscosity, preparations were made, each of 0-93 gm. an increase in the rate of initia­ per cent, of a certain sample of polymethyl methacry­ tion (k-fi) is responsible for the rise in rate of poly­ late in a mixture of 2 c.c. of monomeric methyl metha­ merization of methyl methacrylate, then the chain- crylate and 2 c.c. of diluent (a small amount of hydro- length of polymer should fall throughout reaction, quinone was added to prevent further polymeriza­ for the average chain-length is given by P = tion). Table 3 shows that the bulk viscosities were kjc^ ä£3 ^MG In Schulz’s data there is no very different according to the nature of the diluent. evidence of such a fall during the period of increase T a b l e 3. of rate, notwithstanding considerable temperature increases ; furthermore, in all our experiments (under practically isothermal conditions) we have invariably found an increase of chain-length of polymer through­ out this period, even at 25° C. and 40° C., where catalyst decomposition must be inappreciable. A few typical results are given in Tables 1 and 2, illustrating our findings. In Table 1, P is an index of chain-length The accompanying graph summarizes the changes which took place during the polymerization of the various solutions of methyl methacrylate. None of the diluents was specially purified, and short induction periods were observed before polymerization started, presumably due to small amounts of inhibitor ; the recorded curves are plotted from the end of each induc­ tion period. It will be seen that up to a certain stage in each experiment, the influence of all diluents was similar, but beyond this stage, the rate of reaction rose in a specific manner, in agreement with our views that with a poorer solvent and therefore greater degree of aggregation of polymer chains, the rise in rate should be more marked and occur earlier. the graph it can be seen that the poorest solvents gave the most marked rise in rate and the best solvents scarcely any at all. This parallelism between increase in chain-length and rate of reaction is exactly what we should expect, assuming the termination ‘constant’ k3 to decrease with increasing bulk viscosity of the system. With diluents 1-3, the polymer precipitated as an opaque gel almost at the start of reaction, whereas with the other diluents, precipitation never occurred. We suppose that forces between polymer chains tend to produce association, while forces between solvent and chains act oppositely according to the solvent ‘power’ ; thus, chain association can occur in a single-phase system or in an opaque gel according to diluent, causing a reduction of mobility of the active growing ends and therefore a fall in the rate of termination of chain growth. It seems likely that variation of the rate ‘constant’ of mutual termination throughout polymerization is not confined to methyl methacrylate, though for this substance the effect may be particularly strong since there is probably little opportunity for kinking of the macromolecules *, and thus the mobility of the growing ends of polymer chains may be more sensi­ tive to constraints applied at remote parts. In the literature there are several instances reported of high rates of polymerization and chain-lengths, for example, with polyisobutene at low temperatures’ and in some emulsion polymerizations8, and it is possible that ex­ planations may apply on the lines we have put for­ ward. We ourselves have (incomplete) data suggest­ ing that similar effects may occur to a lesser degree with vinyl acetate and styrene. Time (mill.) 1 Norrish, R. G. W., and Brookman, E. F., Proc. Roy. Soc., A, 171 P olymerization ok d il u t e d m e t h y l methacrylate 40“ C. 40% D iluent (by vol.). 0-0094 m ol.B z,0,/litre. 147(1939). 2 Norrish, R. G. W., Trans. Far. Soc., 35, 1087 (1939). 0 , Undiluted monomer. 1, 2, 3, Precipitants of polymer: 1, butyl stearate ; 2, hep­ 8 Schulz, G. V., and Blaschke, F., Z. physik. Chem., B, 50, 305 (1941), tane ; 3, cyclohexane. 4 Schulz, G. V., and Huseraann,B., Z. physik. Chem., B, 39, 246 (1938). 4, 5, 6, 7, Poor solvents of polymer : 4, amyl acetate ; 5 Gee, G., Trans. Far. Soc., 35, 1086 (1939). 5, n-amyl chloride ; 6, ethyl acetate ; 7, carbon tetrachloride. 6 De Rosset, A. J., J. Chem. Phys., 9, 766 (1941). Tuckett, R. F., 8, 9 , 10, Good solvents of polymer : 8, benzene ; 9, chloro­ paper presented at Far. Soc. Discussion, May 1942. form ; 10, methylene dichloride. 7 Thomas, R. M., Sparks, W. I., and Frölich, P. K., J . Amer. Chem. Soc., 62, 276 (1940). In our experiments witli each diluent* we pre­ * Staudinger, H., and Huseman, E., Ber., 68, 1691 (1935). cipitated two samples of polymer : one during the initial period of slower reaction and the other after the rate of reaction had increased. In Table 4a values of the viscosity index of chain-Iength, P, are ILLUMINATION AND VISUAL given for the former period, and in Table 46, for the RANGE UNDER WATER latter. A comparison of the two values for each diluent By D r. H. H. POOLE shows that the most marked increases of chain-length Royal Dublin Society occurred for the poorest solvents, and scarcely any at all occurred for the best solvents ; referring to N a paper on illumination and visual range under water1, R. Ruedy has given an account of measure­ * It should be recorded that, in our experiments with diluents 4 -1 0 , I about 1 per cent of polymer was present at the start. In order to mini­ ments made with rectifier, or blocking-layer, photo­ mize inhibiting etfects of oxygen, reaction tubes were sealed, and cells by some American and European workers during monomer was kept in vacuo; at room temperature the monomer polymerized slowly. recent years, including particularly a summary of the important work done by Utter back and his co- illumination to 10 per cent in 5-7 and 23 m., respec­ workers in eastern Pacific waters, and by Clarke and tively, this depth being equal to 2-3/(x. As we move his colleagues in the western Atlantic, and a useful inshore [x increases, comparatively slightly for red, bibliography which, however, does not include an much more for green, and even more for blue, so important paper by Le Grand8 or a paper by Atkins that at an inshore station we might get values like and Poole3. 0-5, 0-3, and 0-4 for red, green, and blue respectively. He has also attempted the rather difficult task of In oceanic water, on the other hand, the blue and correlating the results so obtained with the visual green coefficients fall, Clarke having recorded values observations recorded by divers, and given some about 0-05 for the blue-green light at considerable account of photometric measurements made in depths in the Sargasso Sea. The lower layers some­ Beebe’s bathysphere, and of underwater photo­ times are more transparent than those above, so long graphy. as they are not too near the bottom, but frequently In comparing the results obtained by different the water appears to be very homogeneous. workers it is essential to consider the instrumental Utterback also made measurements with a selenium conditions under which they are obtained. It is cell and a filter which reduced its spectral sensitivity always necessary that the cell should be enclosed in to r ear that of the eye, and has given values of the a water-tight case behind a strong window, which is illumination in foot-candles and in lux at various generally horizontal so as to eliminate troubles due depths. By a curious slip, which might be overlooked to the rotation of the photometer, and is turned and thus cause confusion to the reader, the reduction upwards so as to measure the vertical downward to lux has been made by dividing (instead of multi­ illumination. Most workers nowadays place a dif­ plying) the foot-candle values by 10-76. fusing glass above the window, so that the photo­ Comparatively small changes in the value of u will meter may measure the light from a complete cause very large changes in the illumination at hemisphere falling on a horizontal surface ; but this appreciable depths. Thus, a change from 0-08 to has not always been done, and without the diffusing 0-12 (which might readily occur at any coastal glass the photometer, when submerged, is only station a few miles offshore) will reduce the light at sensitive to rays making an angle not exceeding 48° 50 m. from 1 -8 to 0 -25 per cent of the sub-surface with the normal to the surface. This may, in certain illumination. The lower of these values, however, circumstances, have an appreciable effect on the ratio would, on a bright summer day, still be equal to of the illuminations recorded at different levels, and normal daylight about sunset. will certainly reduce the ratio of readings obtained The determination of the angular distribution of with down-turned and up-turned windows, as a submarine daylight is not easy, but polar diagrams considerable part of the upward illumination must have been obtained in comparatively smooth and make large angles with the vertical. The absence of sheltered Swedish waters by Johnson and Liljequist. an opal glass will also increase the apparent loss of These workers found that the enhanced extinction light at the sea surface, a quantity which is not easy of oblique rays caused a reduction of average obliquity to measure accurately except in smooth water. with increase of depth. Whitney has also made such The range of colour sensitivity of the photometer measurements in American lakes, and Atlantic waters, used is also important. Both red and ultra-violet are even as far off as the edge of the continental shelf, extinguished by sea-water very much more rapidly and considers that below 10-20 m. a balance between than green and blue ; thus a selenium rectifier cell the effects of scattering and absorption maintains the without colour filter (which is more sensitive than average obliquity approximately constant. This the eye to both ends of the spectrum) will, in uniform view has also been put forward by Atkins and Poole, water, give a much greater extinction co-efficient who used a cubical photometer containing six cells set near the surface than in deeper layers. The copper in perpendicular directions. They found that, in the oxide cells used by Clarke in much of his work, being waters off Plymouth, below 10 m. there was no relatively less sensitive to the ends of the spectrum, decided change in the ratio of the horizontal to the do not show this effect to so great a degree. Utterback, vertical illumination either with depth or with surface who uses the selenium cell (which appears to be light or conditions, the average obliquity being about more stable than the other), has in most of his work 38° corresponding to a mean illumination on a limited the spectral range employed in each measure­ vertical surface about 25 per cent of that on a ment by means of colour filters inside his photometer horizontal one. At a depth of 5 m. in bright sunlight case interchangeable by an electromagnetic device. this rose to about 67 per cent for a vertical surface Atkins and Poole have also used the combination of in azimuth facing the sun. colour filters with selenium cells in the waters off Most workers are agreed that at a level well above Plymouth. In the deeper layers—say below 20 m.— the bottom the upward illumination ranges from the absorption of the spectrum ends has rendered about 2 per cent of the downward in very clear their effect negligible, and a cell without filter will water to 5 per cent, or more, closer in shore. If we only yield slightly different coefficients from those assume that the average obliquity is approximately obtained with green or blue filters. independent of depth, we readily find from this that When allowance is made for any differences in the only 4-10 per cent of the light cut off in any thin modes of measurement or of presentation used by layer is scattered back through angles greater than different workers there is general agreement between 90°. As scattering through smaller angles has such their results. Thus, if, as is customary, we define an effect in maintaining the average obliquity it the coefficient of extinction u. by the equation must be much greater than this, which seems to indicate that the particles concerned are compara­ — — F, where V is the illumination on a horizontal tively large compared with the wave-length of light. surface at a depth is m., at a point 10 miles offshore, Several workers, including Ruedy, Le Grand, and we might expect to find values for [x rather less than Whitney, have derived formal,b connecting the 0-4 for red light and rather more than 0-1 for blue visibility of objects under water with extinction and and green. These figures correspond to reductions of scattering coefficients. One objection to these is the need for assuming some law of angular distribution suggestion to Archdeacon J. H. Pratt, of Calcutta, of scattered light which may be far from the truth. that he should calculate the gravitational pull of the The visibility of an object which is not too small Himalayas at various stations of the triangulation, depends on the ratio of its surface brightness, as seen, with the view of correcting the observed latitudes. to that of the surrounding field. This ratio must The calculated attractions were greatly in excess of differ from unity by an amount which is almost those indicated by the observations, and led to independent of the absolute brightness (provided Pratt’s well-known theory of mountain compensation, this is not too small), and may. according to Ruedy, and Airy’s equally famous hypothesis of the “roots of be taken as 2 per cent. The chief obstacles to visibility the mountains”. It seemed, then, that at moderate are (a) the reduction of the ratio of brightnesses by or at great distances the attraction of the mountains the addition to both of the daylight scattered by the was for the most part compensated, and that deflex­ intervening medium ; (6) the reduction in absolute ions observed well away from mountain ranges might difference of brightness by extinction in the inter­ be ascribed mainly to local causes, which would have vening medium, including the mixing of light from a random effect on observations made at an evenly the object and field by scattering ; (c) the possible distributed set of stations. reduction of illumination to such a degree that Burrard’s discussion of the accumulated Indian data increased ratios are needed to ensure detection. in 1901 led to an important modification of this view. The extinction of red light reduces all objects to a He found that the local deflexions showed systematic green or bluish green hue a few metres under water. trends in directions parallel to the Himalayas ; nor At greater depths, when the eye is dark-adapted, could their amounts be attributed to any system of colour sensation is lost; visibility is, however, helped mountains and their compensation. It was, there­ by the fact that the maximum sensitivity is then fore, incorrect to suppose that mountain attraction close to the wave-length which is best transmitted did not extend to any great distance, or to treat by sea-water. deflexions as random errors. It is evident that the distance at which an object In 1909 H ayford published the results of his deter­ is visible must vary greatly with its direction. A mination of the earth’s axis and figure by a new light-toned object, such as the Secchi disk, is probably method. Accepting mountain compensation as norm­ most visible against the dark background of the ally complete and assuming that below a depth of water directly below the observer, although here the 113 km. there is hydrostatic equilibrium, he computed intervening scattering particles are more strongly the effect of all topographical irregularities at each illuminated than the object. A dark-toned object station of observation, and applied the result of the should be more visible in a horizontal direction, computation as a correction to the observed latitude, while the visibility of any object overhead must longitude or azimuth, as the case might be. There is, largely be governed by the degree of small-angle therefore, a difference between the smoothed geoid scattering. The presence of direct sunlight would that Hayford was endeavouring to fit and that which introduce azimuthal asymmetry and further com­ had been dealt with in earlier determinations. Hay­ plicate the problem. ford, moreover, uses the data of the United States of It would seem then that, pending further increase America only ; if a similar determination covering in our knowledge of the angular distribution of Australia could be made, the results would be of the scattered light and of the resultant distribution of highest interest. field brightness, it is difficult to estimate with cer­ Dr. R. Stoneley indicated how closely geodesy, tainty the visibility of a given object from measure­ astronomy and geophysics are interconnected. The ments of light penetration alone. connexion between the gravitational field of the earth and its geometrical form is noticed as soon as one ‘ National Research Council of Canada, No. 1061. 1 Ann. d'Inst. Ockan., 19, Fasc. 4 (1939). uses a plumbline or spirit-level. It is natural to a J. Mar. Biol. Assoc., 24, 271 (1940). use as a reference surface a gravitational equipoten- tial, and the equipotential that coincides with mean sea-level is termed the ‘geoid’; since this is not a simple geometrical surface, it is convenient to use THE FIGURE OF THE EARTH for reference a spheroid decided upon by international agreement. In a corresponding way gravity may be GEOPHYSICAL Discussion was held on August compared with a standard gravity formula. The A 14 in the rooms of the Royal Astronomical relationship between trigonometrical work and the Society, when the subject dealt with was “The Figure intensity of gravity is seen in Clairaut’s well-known of the Earth”. formula; the variation of gravity with latitude Sir Gerald Lenox-Conyngham opened the discus­ determines the ellipticity of the figure of the earth. sion with a statement of the values obtained by Airy, It is assumed that the ocean is free from shearing Everest, Bessel, Clarke and Hayford for the semi-axis stress, but no assumption is made concerning the major of the earth and for the ellipticity of figure. distribution of density within the earth. In attempts to eliminate so far as possible the effects A theorem due to George Green shows that a know­ of local deflexions of the plumb-line, Airy avoided arcs ledge of the external gravitational field does not measured in mountainous country, while Everest determine uniquely the density distribution within used only the longest arcs available. The funda­ the earth. None the less, some information of a mentally important question arises as to whether general character is forthcoming from the theory of these local deflexions may be treated as random the earth’s attraction ; if A , A , C are the principal errors ; if so, it is appropriate to use the method of moments of inertia, M the mass, a the mean radius minimum squares in the reduction of the observation. of the earth, and m the ratio of centrifugal force to This was the method employed by Bessel, and the gravity at the equator, then the ellipticity (e) of fact that Airy did not use it suggests that he did not figure is given by J=3(C~A)j2M a2= z — \m. The regard the deflexions as random. num ber J can be found independently from the An important development began with Waugh’s monthly term in the moon’s latitude. The ‘dynamical compression’ (C —A )/C is known from the period of J = J lt and it remains to find the difference between the precession of the equinoxes, and with the pre­ q and q1. The computation made by de Sitter ceding formula leads to the value 0-334 for C /M a2, assumed that the actual earth differs from an ideal whereas in a homogeneous earth the value would be hydrostatic earth in having an excess of mass in the 0 -4. Thus, the earth must on the whole be centrally continents and a deficiency in the oceans ; these mass condensed. Likewise, a knowledge of J and m deter­ anomalies are supposed to be isostatically com­ mines £ with great accuracy. pensated by a ‘compensation’ which is uniformly dis­ A further advance can be made if it is assumed tributed throughout the material above the isostatic that the earth is to a near approximation in hydro­ surface. If the suffix 1 refers to the ideal surface the static equilibrium for forces of long period. The results become : work of Callandreau and of Sir George Darwin then (C'-C 1)/C1= -0-000,000,34 ; H - H ^ -0-030,000,85 shows that, given e , m, and the dynamical compres­ sion, the value of C can be found ; the calculation q — 9i — — 0 *000,000,03 ; e“1- s r ’ = 0-04, indeed is so insensitive to the assumed law of density so that the difference in the ellipticities is entirely that the known ellipticity cannot be used to test a negligible. If there were no isostatic compensation law of density that gives the correct value of <7. the difference in the values of e would have been In spite of the restrictions imposed by Green’s about two units. theorem, one can use observations of gravity over a Astronomical theory gives J = e — 0-0017287 restricted area to derive some information about the = q/P(A + By-'), where P is the processional con­ density distribution a little way below the surface. stant, A and B are known with great accuracy from Some of the mathematically possible distributions theory, and ;j/ depends on the ratio of the masses of involve negative masses, and in practice other the earth and moon. If, then, the assumption is methods, such as seismic exploration, are available conceded that the earth below the isostatic surface is to check gravitational measurements. Within these in hydrostatic equilibrium (and there is evidence that limitations, much scientifically and commercially this assumption is not strictly correct), this method useful information may be obtained. gives the value of the compression with a smaller The Astronomer Royal pointed out that the addi­ uncertainty than any other method. tion of the Callandreau-Darwin theory to the work Dr. E. C. Bullard discussed how far the values of of Clairaut brings in the assumption that the earth 1/e given by various methods agree with de Sitter’s is in hydrostatic equilibrium throughout. Since the result. These values are : actual land surface is not a gravitational equipoten- tial, the validity of this extra assumption requires Motion of lunar perigee 296-6 ± 1-2 critical examination. The justification is due to Motion of lunar node 296-0 ± 1-2 de Sitter, who assumed the earth to be in hydro­ Motion of moon in latitude 297-3 ± 0-9 static equilibrium from the centre up to a surface Gravity observations 296-6 ± 0-5 which he named the ‘isostatie surface’; the undis­ Lunar parallax 294-7 ± 1-4 turbed surface of the ocean was taken to be part of Triangulation (Hayford) 297-0 ±0-5 the geoid, and between these two surfaces the equi- Precession 297-24 ±0-044 potential surfaces would not necessarily be spheroidal, N utation 297-61 ±0-12 nor would they necessarily be surfaces of equal Of these determinations, the lunar parallax method density. If the hydrostatic condition were satisfied depends on measurements at Greenwich and the Cape throughout, the upper surface of the (ideal) body only, and may be suspected of serious systematic representing the earth would be a surface which error. The mean of the first three is 296-7 ± 0-6 ; de Sitter calls the ‘ideal surface’. The spheroid this astronomical determination, combined with that which is the best fit to the geoid he calls the ‘normal from gravity observations, gives 296-6 ±0-4 (A). surface’. Accepting de Sitter’s justification of the use of the If the outer potential of a body which is symmetrical processional method, which involves the assumption both with regard to an axis of rotation and to an of hydrostatic equilibrium, that method is capable equatorial plane is expanded in a power series in 1/r of high precision, and the result differs from the and it is assumed that the surface which is an equi- preceding result (A) by 0-6 ± 0-4. This difference potential surface is nearly a spheroid, the boundary may not be significant, but if the difference is real, it conditions give for a body of the size, mass and implies stress differences of the order of 2 x 107 dynes/ angular velocity of the earth the relations cm.2, which are by no means unlikely. J = e - 0-0017287 ; ß = 0-0086559 - s, Dr. H. Jeffreys recalled his attempt in 1941 to represent the observations of gravity over the earth’s where ß is the coefficient of the term in sin 2

NEWS and VIEWS Centenary of Sir James Dewar Sir James Ivory, F.R.S. (1765-1842) O n September 20 occurs the centenary of Sir James James Ivoby, the Scottish mathematician who Dewar, one of Great Britain’s greatest experimental­ died at Hampstead a hundred years ago on Septem­ ists, occupying as he did for forty-six years the chair ber 21, had the distinction of being among the of chemistry at the Royal Institution and for thirty- first to introduce into Great Britain those methods six years guiding its destinies both by his position and of mathematical analysis which, from the time of his discoveries. Dewar added greatly to the lustre of Leibniz and the Bernouillis, had been gradually the Institution, and by his many investigations, developed on the Continent. The only mathematical especially those on the liquefaction of gases and the appointment he held was that of professor of mathe­ attainment of high vacua, gained for himself a place matics at the Royal Military College then housed among the leading chemists and physicists of his time. at Marlow, in Buckinghamshire. This post he held Bom at Kincardine-on-Forth, he studied under from his thirty-ninth to his fifty-fourth year. The Playfair at Edinburgh and Kekule at Ghent, and at son of a Dundee watchmaker, he was born in 1765, the age of thirty-three was made Jacksonian pro­ studied for six years at St. Andrews and Edinburgh fessor of experimental philosophy at Cambridge. and was then, in 1786, appointed a teacher in a school Two years later he was chosen to succeed Gladstone a t Dundee. In 1789 he abandoned teaching to become as Fullerian professor of chemistry at the Royal partner in a flax mill, and it was on the dissolution of Institution and after another ten years was made the partnership in 1804 that he came to Marlow. He superintendent. The year he went to Albemarle Street gained a wide reputation for his mathematical and had seen the experiments of Cailletet in France and astronomical papers in the Philosophical Transactions of Pictet in Geneva on the liquefaction of the so-called of the Royal Society. He received several medals, permanent gases. including the Copley Medal of the Royal Society, and Following in the footsteps of his great predecessor, with several other men of science was knighted in Faraday, Dewar in the early eighties began his own 1831. He was a corresponding member of the Paris researches on gases which were to lead to many Academy of Science. striking results. He first publicly exhibited liquid air, he obtained liquid oxygen and then liquid hydrogen in considerable quantities ; in 1892 he Soviet Scientific Films invented and freely gave to science and the world the A n u m b e b of Soviet scientific films were presented Dewar vacuum flask and in the early part of the at the Imperial Institute Cinema on September 12 present century discovered, as H. E. Armstrong said, by the Society for Cultural Relations with the “the marvellous power of charcoal to absorb gases U.S.S.R. in conjunction with the Association of at low temperatures ” which “ will render the period Scientific Workers. The films, which covered a wide of 1900 to 1907 ever memorable” . B ut D ew ar’s range of subjects, were of absorbing interest and studies on gases, low temperatures and high vacua high technical quality. They included novelties in are but a part of his researches, which ranged from Soviet scientific and technical practice besides the water to explosives, from atomic weights to spectro­ popularization of well-known facts for children and scopy, from the properties of soap bubbles to the adult lay audiences. The former featured some temperature of the sun. He was elected a fellow of the excellent photographs of the Black Sea Express, a Royal Society when he came to London in 1877, and two-keeled motor sea-glider for passengers, with a lived to receive honours from scientific bodies at speed of fifty miles an hour, Prof. P. Kapitza’s home and abroad. In 1904 he was knighted by King miniature turbine for producing cheaply liquid oxygen, Edward. AbcT9 all else the welfare of the Royal and a clever device for protecting workers at the Institution was his great ambition and anxiety, and forge from heat with a screen of running water which after his death which took place on March 27, 1923, absorbs the infra-red radiation. An artificial fledgling, a bronze plaque portrait of him was placed on the made by children, which automatically opens its staircase of the Institution he had served so long and beak and projects the food inserted by the unwitting so well. mother bird into a bottle of formalin, enabling a = J. & A. C h u r c h il l l t d . = TWELVE SCIENTIFIC BOOKS

A TEXTBOOK OF BIOCHEMISTRY A TEXTBOOK OF PLANT VIRUS DISEASES By A. T. CAMERON. D.Sc., F.I.C., F.R.S.C. New (Sixth) Edition. By K. M. SMITH, F.R.S., D.Sc., Ph.D. 101 Illustrations. 21s. 3 Plates and 25 Text-figures. 18s. RECENT ADVANCES IN PLANT GENETICS THE ADOLESCENT CRIMINAL (Sansome and Philp) A Medico-Sociological Study of 4,000 Male Adolescents Second Edition by F. W . SANSOME, Ph.D., F.L.S.. F.R.S.E. 55 Illus­ By W . N ORW OO D EAST, M.D.. F.R.C.P. In collaboration with trations and 49 Tables. IBs. P. STOCKS, M.D., and H. T. P. YOUNG. M.B. W ith a Foreword by Sir ALEXANDER MAXWELL, K.C.B., K.B.E. 112 Tables. 45s. ALLEN’S COMMERCIAL ORGANIC ANALYSIS PLANT PHYSIOLOGY W ritten by Specialists. Fifth Edition. Complete in ten volumes. By MEIRION THOMAS, M.A. Second Edition. 61 Illustrations. 21s* 36s. each volume.

SYNOPSIS OF HYGIENE PRACTICAL PHYSIOLOGICAL CHEMISTRY (Jameson and Parkinson) By P. B. HAWK. M.S., Ph.D., and O . BERGEIM, M.S.. Ph.D. Eleventh Seventh Edition. By G. S. PARKINSON, D.S.O., D.P.H., Lt.-Col. Edition. 288 Illustrations, 20 in colour. 42s. R.A.M.C. (retd.). 16 Illustrations. 25s. AN INTRODUCTION TO INDUSTRIAL STARLING’S PRINCIPLES OF HUMAN RHEOLOGY PHYSIOLOGY By G. W . SCOTT BLAIR, M.A., Ph.D., A.I.C., with a Foreword by Edited and Revised by C LOVATT EVANS, D.Sc., F.R.C.P., F.R.S. E. C. BINGHAM, A.B., Ph.D., D.Sc. 20 Illustrations. 7s. id . Eighth Edition. 673 Illustrations. 7 in colour. 32s.

THE WAR GASES : Chemistry and Analysis EXPLOSIVES : Their History, Manufacture, By Dr. MARIO SARTORI. Translated from the Second Enlarged Properties and Tests Italian Edition by L. W. MARRISON, B.Sc., A.I.C. 20 Illustrations By ARTHUR MARSHALL, A.C.G.I., F.I.C., F.C.S. Second Edition. and 15 Tables. 28s. Vols. I and II. 157 Illustrations. 63s. Vol. III. 14 Illustrations. 42s.

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High prices also paid for short supply owing to war conditions are University College, Leicas, Contaxes and similar miniature advertised in this Publication should not be Cardiff. cameras.—Wallace Heaton, Ltd., 127 New taken as an indication that they are necessarilv September 12, 1942. Bond Street, London, W.l. available for export.

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232 pages, 9x6, illustrated, 17/6 net J or the photomicrography of stained sec­ N this book the authors’ purpose is to present the essential fundamental tions experience has proved that there is no Iof heat transmission in a treatment that is readily comprehensible and at the same time fairly comprehensive. Emphasis is placed upon acquiring better plate for general use than the Ilford Rapid a clear conception of the manner in which heat is transmitted and upon Process Panchromatic which, when used in con­ development of the fundamental mathematical expressions which apply to the calculations of heat transfer through clean surfaces. The wealth of junction with the Ilford Micro series of colour detailed numerical examples is a feature of the book. filters, allows the tonal differentiation of colour values to be controlled with accuracy. The -C ontents- negatives obtained are remarkable for great Preface Free or Natural Convection brilliance and perfect resolution of detail, exem­ Nomenclature Heat Transfer to Boiling Modes of Heat Transfer Liquids plified by the illustration below. Heat Transfer by Conduction Condensing Vapours Equations for the Calculation Over-all Transfer of Heat The Ilford booklet “ Photography as an Aid to of Heat Transfer by Conduc­ Application of the Principles of tion (Steady State) Heat Transfer to Design Scientific W ork,” provides the research worker Radiation Problems with a concise guide to the selection of photo­ Introduction to the Study of Variable Heat Flow Convection Appendix graphic materials for every scientific purpose, Forced Convection Index and includes a section devoted to the require­ ments of the biologist. A copy will be sent free on request.

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PRINTED IN GREAT BRITAIN BY FISHER, KNIGHT Jt CO., LTD., ST. ALBANS complete register to be made of the foods consumed ous trade contacts. The Institute also has an ex­ by various birds and their consequent effect on crops, tensive reference library and a technical index cover­ gave an example of how children can contribute to ing most of the relevant trade and scientific publica­ scientific knowledge. A film illustrating the effect of tions issued during the past thirty years. The energy expenditure on blood circulation and showing Institute can deal with inquiries relating to sources the function of the spleen, and a clear exposition of of supply of, and other information relating to, Lena Stern’s method of treating shock extended the raw materials and semi-manufactured products programme to the field of medicine. whether of animal, plant or mineral origin in The final film, “Experiments on the Revival of all countries, cultivation of crops and the soil and Organisms”, was undoubtedly the most impressive. conditions under which they have to be grown, After a brief and exceptionally clear pictorial explana­ methods employed in mining, smelting and dressing tion of the function of the heart and lungs, the film minerals for the market, and so on. Analysis and leads up from the artificial setting in motion of an testing of samples of raw materials is undertaken in the individual organ, the heart, to the revival of a dog’s laboratories of the Institute. Inquiries should be made severed head and finally to the revival of the animal in the first instance to the Intelligence Section of the itself, from which the blood has been completely Plant and Animal Products Department or of the drained off and the heart-beats and respiration of Mineral Resources Department, according to the which had ceased for ten minutes. The blood is nature of the subject concerned. No charge will be re-circulated by means of an artificial circulatory made for services to Departments of the United system, the ‘autojector’, the deceased animal heaves Kingdom Government or other Governments of the its first sigh, heart-beats and respiration begin to Empire contributing to the general funds of the register, and, after a short time, the autojector is Institute unless a particular inquiry involves a volume disconnected and life proceeds. Within a few days of work so great that it cannot be undertaken by the dog is its normal self again and, as the film the existing staff. shows, “lives happily ever after”. The producers are to be congratulated on the skill and beauty of The Rockefeller Foundation this film, which, while maintaining full scientific D u r i n g 1941 the Rockefeller Foundation appro­ clarity throughout, nowhere offends the aesthetic priated more than nine million dollars for public senses, opens up an unlimited perspective of scientific health, medical sciences, natural sciences, social advance and cannot fail to instil into the most sciences, humanities and a programme in China. The unimaginative minds a profound respect for scientific work in public health received the largest appropria­ effort and achievement. The commentary to the tion—2,450,000 dollars. Medical sciences came next films was prepared by Prof. J. B. S. Haldane. with 2,120,000 dollars. The Foundation distributed Mr. Arthur Elton, in his opening remarks, dwelt 1,938,300 doses of yellow fever vaccine to the United on the systematic way in which the popularization States Government and 1,972,386 doses to Africa. of science is treated in the U.S.S.R. and stressed the Including the total sent to India, Brazil and Singapore, necessity of a scientific approach on the part of the the Foundation gave a grand total of 4,260,680 doses whole population in the interests of the maximum of its own manufactured yellow fever vaccine. The war effort. This view was expanded in an introduc­ Paris office of the Foundation closed in Ju ly 1941, tory lecture by Dr. M. Ruhemann, who pointed out and there are now no Foundation representatives on that, in the U.S.S.R., the diffusion of scientific know­ the Continent of Europe, though an office is being ledge and a scientific approach to life has always m aintained in London. The F ar E astern office was been considered a matter of urgent necessity, whereas removed from Shanghai to Manila late in 1940. we have tended rather to regard it as a luxury. Important studies are being carried out in Malta, Reviewing Soviet methods of popularizing science, in in Trinidad and on the Burma Road. books, newspapers, in children’s clubs and on the collective farms, he directed attention to the lack of scientific and technical knowledge among young Detection of Cracks in Engineering Materials people in Great Britain, due to a large extent to an A v a l u a b l e development in the use of fluorescent antiquated school curriculum, and to the tragic light is its application to the detection of flaws or consequences which this is bound to have on the cracks in engineering materials, and a demonstration efficiency of our Forces in a highly mechanized war. showing its effectiveness was recently given by Mr. D. N. Pritt moved a vote of thanks to the speakers Colloidal Research Laboratories, 66-70 Petty and the promoters of the meeting, which was so well France, London, S.W.l. Their ‘Glo-Crack’ system, supported that large numbers had to be turned away. as it is named, marks a great advance on existing A repetition of the exhibition is being considered. methods and makes the detection of the least visible form of crack as nearly as possible a certainty. The articles to be examined are first immersed for a short Imperial Institute period in a hot bath of fluorescent material. They T h e extensive facilities available at the Imperial are then transferred to a second bath containing a Institute, London, S.W.7, for the rapid supply of solution which removes all the fluorescent material technical information relating to the trade, occurrence except that which is entrapped in any flaws or and utilization throughout the world of all kinds of cracks. This part of the process is very much the raw materials, and the scope of the intelligence service same as the familiar one of degreasing and, as a are not so well known as they should be. The secondary advantage attached to the new process, Institute’s staff includes tropical agriculturists, it may be mentioned that the hot bath is actually chemists, chemical technologists, economic botanists, an efficient degreasing agent. economic geologists, mining engineers, mineralogists After this preparation, each article is examined and statisticians, and, when desirable, the Institute under ultra-violet light and every small flaw or seeks the advice of members of its fifteen consultative crack glows with the characteristic colour while the committees. Further help is also afforded by numer­ remainder of the specimen remains dark. In this way a crack, no matter how fine, can scarcely vided they are suitably interlocked—especially where escape detection, Bind this is attained without severe elevators and conveyors work in conjunction—would eye-strain or mental fatigue on the operator. Other prove a great advantage. Again, the sugar house advantages which the demonstration exhibited are should be equipped with the best type of sugar- its applicability, without staining or the necessity for spinning centrifugals. Much has been done by the after-treatment, to all metals and to many other manufacturers in conjunction with the users to materials, its simplicity and cheapness of operation, improve this class of machinery. and the quickness with which the process can be carried out, even on mass-produced articles. The Electrified Cane-Sugar Factory While the normal technique is that of dipping in the fluorescent bath, this can be varied to suit special In a paper on this subject (J. Inst. Elec. Eng., 89, cases. An exhibit of special interest was a flaw in P t. 2, No. 10; Aug., 1942) L. B. W hitaker deals the interior of the base of an aeroplane propeller with some of the considerations relating to total blade. The hole had been sprayed with the fluorescent electrification of such factories, with special reference solution and after being washed out, the insertion of to the factory at Gray’s Inn, Jamaica. Reasons are a black lamp showed the flaw glowing clearly with cited for the slow adoption of the totally electrified fluorescent light. This obviously valuable scientific sugar factory in the British Empire as compared process was shown in its adaptation to the practical with other parts of the world. A brief general descrip­ requirements of engineering, but its great possibilities tion of the processes involved is then given, advan­ suggest a much wider field of application both in tages and disadvantages being discussed and some scientific investigation and industrial development. comparison drawn with steam-driven plants. The necessity of having a sugar factory specially designed Magnetic Crack Detectors for all-electric drive is then stressed, and details are given of the general layout of such a plant to obtain A n article in the Electrical Review of August 28 the maximum benefits of total electrification. The describes a magnetic detector used to .facilitate crack most suitable type of apparatus to employ is dis­ detection in motor and aero-engine parts. While cussed, including notes on power-factor correction radiographic methods of crack and blow-hole detec­ and maintenance routine. The paper concludes with tion possess undoubted advantages when the flaw examples of typical power consumption and cost of lies below the surface, for superficial cracks and generating current. defects as much as J in. below the surface, the magnetic crack detector offers advantages in the speed and economy of its application. The general Rural Electrification and Research principles of the method have been described in An article by A. G. H . D ent (Electrician, August 21) the Electrical Review of April 4, 1940. They consist surveys the necessary and probable trend of rural briefly of subjecting the part under test to a magnetic electrification and research in Great Britain during the field and applying a magnetic powder, or a liquid post-war construction period. The author opens with medium containing such powder, to the suspected a reference to the national education in food values surface, so that any polarity due to a crack is rendered and uses. The national neglect of agriculture is visible to the eye by collection of the magnetic ended, and any positive reconstruction policy must particles over it. incorporate broad measures of industrial decentraliza­ The crack detector described, known as the ‘Magna- tion of agricultural development and of food—or flux’ (Equipment and Engineering Co., Ltd.), pos­ health-education. The article proceeds to define the sesses the special feature of sliding laminated pole position and responsibility of the public utility tips between which the object is mounted for company in such a scheme, stressing that the words inspection. A few seconds only are needed to adapt ‘public utility’ imply usefulness to the public as a them to objects of almost any shape by merely national service forming an essential part of the sliding the laminations up to the contour of the social structure. specimen. A further feature is that means are pro­ The recent introduction into farming of a minimum vided for controlling the magnetizing current, which wage for agricultural labourers of £3 per week is is important on account of the need for avoiding cited as an incentive for electrical methods of carrying supersaturation, or insufficient saturation. There is out farming operations on a continually increasing an optimum degree of magnetization giving the scale ; with such a demand will come the need for most readily seen and crisply defined crack outlines. electrical apparatus and machinery for doing the Demagnetization of the tested parts is effected by work. During the last few years, root cooking by laying the objects on a horizontal platen magnet, or electrical methods has been successfully employed, subjecting them to an A.C. field : demagnetization is while the electric wash boiler has found application practically instantaneous. in the boiling of potatoes. There appears to be a demand for a cheap, low-loaded apparatus, of 1-3 kw., Electricity in a Beet-Sugar Factory designed especially for root cooking. Bottle washing, B. S m i t h has described (J . Inst. Elec. Eng., 89, herb drying, and the provision of hot water for feeds P t. 2, No. 10 ; Aug., 1942) the application of elec­ and mashes are also quoted as more recent uses of tricity in the treatment of sugar beet through all the electricity in farming. stages to the ultimate production of pure sugar. Mention is made of a G. E. C. (U.S.A.) experiment Although many factories in Great Britain have in which fruit trees and seeds are bombarded by applied electricity in the best manner possible within X-rays in an attempt to improve the size, quality their limited expenditure, yet both in the factory and and flavour of the fruit. It is thus evident that a in the laboratory there still remains much room for technique may be developed for the more intensive further improvement. For example, individual drives electrification of agricultural processes and that could be installed in many places where at present changes may be brought about gradually in farming one large unit and line shafting now exist, and pro­ methods. Epidemics in English Villages delay and with an effective current through the regulating contacts of about two microamperes. The I n his Milroy Lectures for 1942 before the Royal same instrument may also be used for high speed College of Physicians (Univ. Leeds Med. Magazine, machine timing operations, or the regulation of 64, 12 ; 1942) Dr. W. N. Pickles, the energetic temperature, pressure, humidity or hydraulic flow. medical officer of health for Aysgarth in Yorkshire, As an example, a laboratory type of constant tem­ chose for his subject “Epidemic Disease in English perature bath is available, in which the accuracy of Village Life in Peace and War”. He makes a strong regulation is better than ± 0-01° C. Another type appeal to country doctors to follow his example is a liquid level regulator, with no float or other in keeping diligent records, preferably in chart form, moving parts within the container ; this is particu­ of various epidemics in their districts such as in­ larly suitable for use with electrolytes, and the fluenza, scarlet fever, measles, German measles, electrodes may be a fraction of an inch apart or mumps, acute rheumatism and cholera, summer several feet from each other. An electronic ‘stop­ diarrhoea, epidemic jaundice and epidemic myalgia, watch’ records time intervals up to 2,000 seconds in the last being a disease which Dr. Pickles was one intervals of a fifth of a second. It seems likely that of the first in Great Britain to describe. Contrary to these and other similar devices will find widespread what he had expected, Dr. Pickles has so far not application to laboratory and industrial processes. found that war conditions have caused an increase of epidemic disease, although village life has changed to some extent owing to the immigration of town Ice on Conductors children. Since the outbreak of the War there has F r o m time to time overhead lines fail by mechanical been no scarlet fever or infantile paralysis in the overstresses alone, due to excessive ice loading. These Aysgarth district and only a few cases of measles deposits have been widespread, and in view of the and cerebrospinal fever, while the only epidemic due severity of recent winters, J. McCombe (Elec. Rev.. to an evacuee was one of jaundice, of which there Aug. 21) suggests that an amendment of the Elec­ were fourteen cases. The chief sources of annoyance tricity Commissioners’ Overhead Line Regulations were impetigo, vermin and scabies, but these were EI. C. 53 (revised) is necessary. The suggestion is soon brought under control. supported with the following observations and criticisms. In the first place the selection of a different Public Health Research basic loading for high- and low-voltage lines is very much open to criticism since wind and ice loading are A c c o r d i n g to an annotation in the Journal of the functions of exposure and altitude and definitely not American Medical Association of July 25. the Health of line voltage or conductor size. Deposits on over­ Research Institute of tho City of New York will head lines in exposed places are more or less constant receive a million dollars a year for ten years for irrespective of voltage. If a better standard of con­ researches on public health. The City and the Insti­ struction is desired, then the more logical method tute, which is a non-profit scientific institution, have would be to adopt a higher factor of safety of erection. entered into a contract which came into effect on Low-voltage lines with the same ice coating will July 1 and is automatically renewable for similar always have a greater security owing to the shorter periods. The money is to be used to carry on funda­ span-length employed. mental medical research under the direction of a In the Regulations referred to, assumptions have research council composed of authorities in medicine, been made to simplify the problem of ice loading. biology, physiology, nutrition, public health and The ice is taken as forming a true annulus around related subjects. Under the contract the services to the conductor. The author’s observations are that be rendered by the Institute will include the following : ice is never deposited evenly or uniformly, either in (1) investigations into the control of diseases such as wind or calm. Its nature depends to a great extent influenza, poliomyelitis, arthritis, degenerative dis­ on the prevailing wind and atmosphere. In wind, eases and general physiological problems; (2) ice tends to form thickest in the leeward side of the engagement in laboratory experimentation in order conductor. Windage helps to build up ice deposits, in to develop better and more economical biological as much that each particle of sleet imparts kinetic products and improved technical procedures for use energy due to the wind and is responsible for the in controlling diseases and epidemics ; (3) aid to the heavier deposits being driven to leeward. It probably director of the Bureau of Laboratories of the Depart­ also accounts for the different ice densities encoun­ ment of Health in matters involving public health tered on overhead lines. The worst deposits, however, research. are due to fog, not to wind and sleet. The heaviest Electronic Relay Control deposits result from fog in the presence of a light wind, when icing is worst on the windward side of O n e of the more useful by-products of the rapid the conductor. It is thought that the fog precipitates development of radio technique is the use of thermionic ice as soon as it finds a metal anchorage. Such ice valves as relays of negligible input power, freedom usually has a heavy, solid core, but becomes fuzzy from contact troubles and practically instantaneous and less dense on the surface. The article concludes operation. These features are utilized to the full in with the suggestion that grading or zoning of the the series of devices and instruments now marketed country, according to climatic conditions, would be by Messrs. St’r Electronic Controls, 76 Cavendish advantageous, and by way of illustration describes Road, London, S.W. 12, as the result of considerable the way this is done in the U.S.A. experience. One of the devices comprises an electronic relay operating on the usual alternating current supply of 230 volts 50 cycles per second, and giving Recent Earthquakes an output of either 200 or 1,000 watts, the latter A c c o r d i n g to the Swiss Seismological Bulletin for being capable of starting a \ h.p. motor on 230 volts June 1942 ju st received from Zurich, twenty-one A .c. supply. This operation is obtained with no time earthquakes were registered by the seismographs at Chur, Basel, Neuchätel and Zurich during the month. Announcements The following have not been mentioned previously S i r R o b e b t R en*w i c k has been appointed to the in the columns of N a t u r e : An earthquake on June 1, newly created post of Controller of Communications registered at Chur at 09h. 04m. 11.7s. u .t ., which came apparently from an epicentre near the Presse Equipment in the Ministry of Aircraft Production, Griechenland. The earthquake of June 20 which and will become a member of the Aircraft Supply Council. He will be assisted by Sir Robert Watson registered at Chur at 14h. 42m. 01 -8s. u .t . came probably from Trentino, Valle Judicaria, in Italy. Watt, as vice-controller. Sir Robert Renwick has The earthquake of June 25, which registered at Chur also been appointed controller of communications in the Air Ministry, where Sir Robert Watson Watt at 22h. 13m. 13-9s. u .t ., came apparently from an epicentre at Mürtschenstock, Kt. Glarus, Switzerland, will continue to hold the appointment of scientific and was felt with intensity IV-V. adviser on telecommunications. These arrangements will ensure still closer co-ordination between the two The earthquake of August 24 in Peru (N a t u r e , September 5) was registered at Kew at 23h. 03m. 36s. departments in this important field. u .t . and attained a maximum ground amplitude at Kew of 1,520 (x. The earthquake of August 27 T h e following appointments in the Colonial Service in the Balkans (N a t u r e , September 5) was also have recently been made : P. H. Richards, agricul­ registered a t Kew at 06h. 18m. 16s. u .t . and tural officer, Nigeria ; B. J. Silk, agricultural officer, attained a maximum ground amplitude at Kew Gold Coast ; M. P. Ford, veterinary officer, Kenya ; of 210 )j.. A. E. G. M arkham, veterinary officer, Kenya ; C. O. T h e United States Coast and Geodetic Survey in Oates (agricultural officer), senior agricultural officer, co-operation with Science Service and the Jesuit Kenya ; K. Wallis (government analyst, British Seismological Association has determined the epi­ Guiana), government chemist, Uganda. centres of several recent earthquakes near South America. These determinations have been based on A r i s i n g out of a recommendation made to the instrumental reports from fifteen observatories. Alto­ Council of the British Association at the conclusion gether there are seven shocks, six being near latitude of the Conference on European Agriculture, a com­ 0-8° N., longitude 80-5° W., which is just off the coast mittee has been appointed, under the chairmanship of northern Ecuador in South America. The dates of Sir John Russell, to collaborate with the Allied of the shocks were all in July— 4 (2), 5, 7, 8 and 12. Technical Advisory Committee on scientific problems The seventh earthquake was on July 8, and its epi­ connected with the post-war reconstruction of agri­ centre was near latitude 25-5° S., longitude 79-5° W., culture in the devastated and oppressed areas of which is in the bed of the Pacific Ocean off the coast Europe. The Council of the Association has also of Chile, and north-east of the islands of San Felix appointed a committee, under the chairmanship of and San Ambrosio. Dr. Dudley Stamp, with the view of strengthening the applications of science (for example, geology, Data for Radio Engineers geography, ecological botany and zoology, soil science, agricultural economics, and forestry) to rural planning A s m a l l publication (Reference Data for Radio in particular. Engineers. Pp. 60. Standard Telephones and Cables, Ltd., 63 Aldwych, W.C.2. 2s.) should find a ready T h e first lecture in the autumn programme of the appeal to all radio engineers, whether they are en­ thirtieth annual series of Chadwick Public Lectures gaged in replacing a small fixed resistor in a wireless will be given at the Royal Society of Tropical receiver or a piece of laboratory apparatus, or work­ Medicine, 26 Portland Place, London, W.l, on ing on the design of a world-wide radio telephone October 6, at 2.30, when Sir Leonard Hill will lecture service. The data included in this booklet have been on “The Inter-Relation of Clothing and Shortage of selected as a result of the experience of engineers Fuel in Matters of Health”. Sir William J. Collins, engaged in the development of radio communication chairman of the Chadwick Trustees, will preside, and systems during the past twenty years. A very wide shortly before the lecture (at 2.15 p.m.) will present field is covered including electrical and mechanical the Chadwick Medal and Prize to Mr. Wilfred constants, properties of materials, circuit theorems, Glyndon May of University College, London. impedance operators, abacs and other data of every­ Admission to all the lectures is free and tickets are day utility to those conducting design and develop­ not required. ment work. A noteworthy inclusion is that of wave propagation curves summarizing the best technical knowledge available at an international conference T h e Medical Research Council invites applications held in 1938. The above material is supplemented from medically qualified women for a studentship for by a generous amount of mathematical formula:, and training in methods of experimental psychology; the usual tabulated quantities up to and including preference will be given to candidates who have had tables of Bessel functions, the need for which has some special training in physiology or neurology, or grown so rapidly of recent years in connexion with who have already had some experience in the use of phase- and frequency-modulation systems. Since the research methods. The studentship will be tenable effectiveness of any communication link, land-line or for six months, during which the holder will receive radio is nowadays expressed in terms of the ratio of training under the direction of Prof. F. C. Bartlett at the wanted signal to the noise-level, it is only natural Cambridge. Payment will be at the rate of £350 per to find a few pages devoted to noise determination annum and the student will be expected to give her and measurement, and charts showing the relation­ whole time to the work. Further information can be ship between the European and American units in obtained from the Secretary, Medical Research the standardization of noise measurement. The refer­ Council, c/o London School of Hygiene, Keppel ence book is a commendable effort in a comparatively Street, London, W.C.l, to whom application should new field. be made by October 5. LETTERS TO THE EDITORS following »»-diphenyl benzene frequencies obtained by one of us8 and S. Abdul Aziz. These frequencies The Editors do not hold themselves responsible are a t 1607(4), 1350(0), 1241(4 br.), 1039(1), 1000(10), for opinions expressed by their correspondents. 611(3), 406(3), 238(3 diff.), 151 (2diiif. and br.) and No notice is taken of anonymous communications. 80 (4 diff. and br.) cm.-1. The strongest frequency of triphenyl benzene, Raman Spectrum of 1,3,5-Triphenyl Benzene observed at 1003 cm.-1, is found equally strong in m-diphenyl benzene and is also present in all the other In two previous communications1 one of us has compounds of this series. But the marked dissimilar­ reported investigations on the structure and Raman ity is that the very strong line at 1309 cm .-1 observed spectra of some of the polynuclear aromatic com­ in m-diphenyl benzene and almost equally strongly in pounds, and we have also submitted elsewhere2 de­ all the other compounds of this series is found to be tails of the results on the ortho-, meta- and para- completely missing in this compound. The other diphenyl benzene. In continuation of those investiga­ very marked difference is that the stronger frequency tions we have studied the Raman spectrum of sym­ of the doublet at 1597 cm.-1, also found in all the metrical triphenyl benzene, in solution in carbon compounds of this series, is not observed in triphenyl disulphide and carbon tetrachloride and also in other benzene. A few of the other lines observed here suitable solvents. The melting point of this substance are also present in benzene and are therefore due to is fairly high and it presents the difficulty that as its the vibration of the benzene ring. The line at 88 cm.-1 temperature is raised to its melting point it tends is due to the molecule itself, although the frequency to become unstable and decompose. is very low as the substance was studied in dilute Two of the spectrograms of the substance taken solution. in solution using a Füess glass spectrograph and some These results are expected to give a clue to the suitable filters are reproduced here. The substance symmetry and nature of the disposition of the sub­ is highly fluorescent under the total radiation of the stituted phenyl groups of this compound. mercury arc, but it will be seen that owing to the Further work is in progress, and a discussion of the large diminution in the intensity of the 4046 A. bearing of these results on the nature and symmetry group of mercury lines, the fluorescence is not appre­ of the benzene rings of this compound will be pub­ ciable and the background is quite clear. The fre­ lished elsewhere. quencies observed and found common in both carbon S. K. M u k e r j i . disulphide and carbon tetrachloride solutions are L a k s m a n S i n g h . a t 3046(1), 2036(4)?, 1603(8), 1496(1), 1350(6 br.), Physics Department, Agra College, Agra. Ju n e 26. 1 Mukerji, N a t u r e , 142, 477 (1938); also Mukerji and L a k s m a n Singh. N ature, 144, 382 (1939). 1 Mukerji and Aziz, Ind. J. Phys., 13, P t . 3 (June, 1909). 3 Mukerji and Aziz, Phil. Mag., (7), 31, 231 (March, 1941).

Formation of a Double Crystal Aggregate and the Structure of the Intermediate Tem­ perature Modification of N i(N 03)2.6NH3

A b o u t five years ago I made an X-ray study in Manchester, under Sir Lawrence Bragg’s kind super­ vision, of the structure of Ni(N03)2.6NH3 at different a, triphenyl benzene in CS, solution ; 6, triphenyl benzene in temperatures. Three modifications were observed CC1, solution. and the structure of the room temperature modifica­ tion was determined1. Attempts were made without 1238(4), 1045(£), 1003(10), 603(1), 406(1), 234(1), success to find the structure of the intermediate 170(5), 146(6) and 87(4 br.) cm .-1 respectively (in­ temperature modification on the assumption that the tensities are given in brackets). A few more lines structure had the symmetry (F43ra, F43, or Fm3m) have also been observed in acetic ether and chloro­ shown by its X-ray photographs. It was not until form solutions at frequencies 2987(4), 1458(5) and three years had elapsed that an idea of the partition 384(5) cm.-1. As the excitation of these lines was of a single crystal into a double crystal aggregate due to X 4358 alone, it is expected that the assign­ came to my mind, and hereupon a structure was ment is free from error. obtained which can explain very naturally and The most significant points of resemblance were satisfactorily all the X-ray intensity data of more found with the spectra of m-diphenyl benzene, which than 300 reflexions. In view of the interest in the consists of three benzene rings, two of these being mechanism of the conversion from the room tem­ substituted in the third in the meta position. Sym­ perature to the intermediate temperature structure metrical triphenyl benzene consists of four benzene and in the formation of the double crystal aggregate, rings, three of which are substituted in the fourth it is thought probably opportune to give a brief in positions 1, 3 and 5. Loss of any one of these account of the work here. three benzene rings converts the substance into The intermediate temperature modification of m-diphenyl benzene. The close agreement between N i(N 03)2.6NH3 is obtained by cooling the crystal the majority of triphenyl benzene frequencies and grown at room temperature by a stream of liquid those of TO-diphenyl benzene will be found in the air falling on it at a suitable speed. The modification belongs to the cubic system, like the room tempera­ khl on the photographs taken with the crystal oscil­ ture modification ; its structure also consists of flat lating about the [001] axis. Thus the symmetry triangular N 0 3 and octahedral Ni(NH3), groups inter­ shown on the photographs is not the actual sym­ locking one another into a CaF2 grouping. Unlike metry of the structure. Since the crystal is neither the room temperature modification, however, the a single crystal nor an ordinary polycrystalline mass, NO 3 groups in the present structure no longer execute I tentatively call it a ‘double crystal aggregate’. A any abnormal oscillation, but assume either one of schematic representation of a section of the aggre­ two alternative configurations roughly corresponding gate perpendicular to the [001] axis is shown in Fig. 2. to the two extremities of an oscillatory NOa in the room temperature structure1. Now suppose that at the very beginning of the conversion of the modifica­ tions from the room temperature to the present, a particular N 0 3 group in the crystal, owing to the loss by cooling of its oscillation energy, assumes one of the two alternative configurations. The change of the state of this N 0 3 group will immediately bring about a modification of the configurations of its neighbouring NH 3 groups ; the modification so caused then in turn makes the other neighbouring N0 3 groups assume the more probable of the two alternative configura­ tions. These N 0 3 groups then cause their own neigh­ bours to change their positions, and the propagation of this process finally results in a structure which The discovery of the aggregate leads us to the has the space group P a‘i. I f the N 0 3 group which following considerations : starts the conversion assumes the other one of the (1) The determination of the space group of a two alternative configurations, the resulting structure structure must be made with due consideration of is the same as the one just mentioned, except that the possibility of the formation of an aggregate of the orientation of the second structure, when looked double or even similarly defined triple crystal when at along a cube axis, differs by 90° from the first one. the X-ray oscillation photographs used for the space In Fig. 1 (a) and (6) are shown the alternative con­ group determination are taken with the crystal at a figurations of a N 0 3 group the original configuration temperature different from the one at which the of which in the room temperature structure is shown crystal is grown. in Fig. 1 in reference (1). (2) It might be expected that the crystalline grains in some polycrystalline metals * are really not single crystals but composed of aggregates of the pre­ ceding kind, if the metals cooled down at a moderate rate from a high temperature have their struct­ ures at the final temperature bearing a favourable geometrical relation­ ship with their structures at the initial temperature. Since numerous new intergranular boundaries must exist within each aggregate we naturally raise the question as to the nature of these new boundaries. If they are of the same nature as the ordinary intergranular bound­ aries, we should expect a metal to be hardened by the formation of a Fig 1. such aggregates. Since the formation is brought about by a mechanism Now let us consider the conversion process taking (not necessarily involving any abnormal oscillations place in the whole crystal. We first expect that the of some atom groups in the initial structure, of conversion must be started simultaneously and inde­ course) totally unknown before, and the resulting pendently by a considerable number of N0 3 groups product of the formation is in a quite stable state, in the crystal, like the solidification of a melt being the study of this formation in metals would intro­ started by the growth of grains from numerous nuclei duce a new type of hardening process in physical in the melt. However, the nuclear NOa groups here metallurgy. On the other hand, if the new boundaries can assume only two possible configurations instead differ in their physical properties from the ordinary of any random orientation, the consequence of which ones, a study of this difference might add some know­ is that the resulting crystallites, after the conversion ledge to the understanding of the nature of the latter. is completed, must have their crystal axes confined Again, we might have the question of whether these to two mutually perpendicular directions, that is, the new boundaries have anything in common with the directions of the axes of the original single crystal. boundaries between blocks of the mosaic structure Furthermore, the external shape of the crystal is not of a crystal. Finally, I should remark that the new changed. On these accounts, the spots on the boundaries cannot be detected either by the etching oscillation photographs of this crystal appear as if and microscope method or by the X-ray method of they were reflected from a single crystal, except that the powder photograph. each spot is a superposition of two reflexions hkl and A detailed account of this work will appear elsewhere. I wish to express my sincere thanks to Sir Lawrence The gross distortion of subjective space in the Bragg for his suggestion of this problem and for the region of the blind spot, because of the lack of sense- keen interest he took in the work ; also to Mr. P. Y. cells in the optic disk, is well demonstrated by the Hwang, who made the final adjustment of the para­ subjective filling in of various incomplete figures made meters in the structure. to fall across the blind spot, as described by Helm­ S. H. YÜ. holtz and others. Metals Research Institute, A binocular phenomenon which I have recently National Tsing-Hua University, observed has some bearing on this and related ques­ at present at Kunming, tions. If a stereoscopic photograph is examined, first Yunnan. so that the relief stands out, and then by inverting Juno 28. so that although the two halves fuse there is no 1 k’ii. N atu re, 141, 158 (1838). stereoscopic effect, the objects in the picture appear to increase in size. If one eye is then closed, the original sizes return. Reversing the procedure gives opposite effects. Mechanism of Metallic Friction An arrangement of mirrors was set up so that the D r. B o w d e n and his collaborators1 in their investi­ right eye would see from the point of view of the left gations on the mechanism of metallic friction need eye, and the left eye that of the right, so that binocular have little doubt that, under many of the conditions fusion without relief would be obtained. Observers of load and .speed used in practice, the local tem ­ were asked to judge the lengths of slips of paper held peratures reach a high value. Very high local tem­ successively in the field of view, first with one eye peratures are attained in very short intervals of only and then with both eyes. Estimates of size in time, as those who have observed ‘seizure’ taking the two cases were in the ratio of 3 to 4; that is, place between the cylinder or liner and piston in an there is an apparent magnification in area of almost internal combustion engine can testify. The oppor­ two. tunity of witnessing this occurrence is rare in modem It would seem that binocular fusion without engine design with closed crank cases, but in the stereoscopic effect is equivalent to doubling the days of the horizontal gas engine, with the open- numbers of active sense-cells and consequently the ended cylinder and trunk type piston, high tem­ subjective size, while where stereoscopic vision is con­ perature, often a white heat, was frequently observed cerned some sort of unification of corresponding when ‘seizure’ took place. sense-cells in the two eyes takes place so that they Probably at that time before the days of ground behave as one—a possible explanation also of finishes, ‘seizures’ on the test bed were a more frequent Fechner’s paradox. occurrence. The dimensional accuracy of the ‘fit’ S h a u n M. C o x . allowances, in addition to the character of the wearing Low Gables, surfaces, which were finish turned and bored, con­ Durham. tributed to this state of affairs. Engineers certainly Ju ly 25. relied very much more on ‘running in’ to establish 1 Bartley, S. H., “ Vision : A Study of its Basis” (London : Macmillan satisfactory working surfaces. I recorded some and Co., Ltd.), p. 114. observations on these matters in a paper before the Manchester Association of Engineers in 1916. Examination of ‘seized’ surfaces of cylinders, Role of Adenine Nucleotides and Growth pistons and rings showed ‘flowed’ failures, and I well remember our chief engineer in those days being Factors in Increased Proliferation following profoundly convinced that such layers had been Damage to Cells molten and consisted of metal melted during the Stim ulation to tissue repair in wound healing has ‘seizure’. been attributed variously to polypeptides and amino- Ashleigh, H u r s t . acids1, sulphhydryl compounds2, nucleoproteins3, Trent Valley Road, fatty acids4, or certain nucleic acid derivatives5, and Lichfield, Staffs. it has been proposed that the stimulating substances 1 See N a t u r e , 160, 197 (1942). are secretions of leucocytes (“trephones”1) or dam- aged-cell disintegration products (“wound hor­ mones”13). Since cell secretions or damaged-cell pro­ ducts influence normal cells through the intercellular Shape of Subjective Space milieu, a direct and quantitative approach to this I n a discussion of blind spot phenomena, Bartley1 problem is afforded by the comparison of inter­ raises the question as to whether points subtending cellular fluids from damaged cells (I) and from equal visual angles are subjectively equally separ­ normal cells (II), with regard to their chemical com­ ated, and suggests that the form of subjective space position and effects on cell metabolism. Such com­ is related to the density of the rods and cones in parisons have shown that (I) greatly exceeds (II) in the retina. stimulating cellular proliferation6»7 and respiration8-9 A theory that each sense-cell (or rather each fibre and in increasing capillary permeability10, and that of the optic nerve, where more than one cell converge when (I), but not (II), from animal tissue sources is on to one fibre) contributes equally to the formation injected repeatedly into animals, overgrowths result7. of subjective space would find much evidence to In the following experiments, cell-free, injured-cell substantiate i t ; for example, the apparent uniformity suspension fluids (I) and normal-cell suspension of the brightness of the visual field, in spite of the fluids (II) from yeast suspensions (S. cerevisice, F. B. variations in population of sense-cells in the retina ; Strain, 100 gm. per 1. in distilled water) were com­ variations in subjective velocity of bodies moving at pared. Injury was by 8 hr. sublethal ultra-violet constant velocity in the field of vision, etc. irradiation11, which produced negligible cytolysis, but caused marked increase in the permeability of the acids resulted in increased growth somewhat greater damaged cells, accompanied by loss of turgor and than that obtained by addition of (I). shrinkage in cell volume (ca. 30 per cent). Both Assays of (I) and (II) for known growth factors17 (I) and (II) were substantially free from protein, as showed appreciable quantities of biotin, pantothenic in previous experiments“ (negative biuret and phos- acid, pyridoxine, nicotinic acid and folic acids in photungstic acid tests and negligible 2700-2800 A. (I) but not in (II). Preliminary tests (not regarded absorption characteristic of proteins, tyrosine or as final) for diphospho- and triphosphopyridine tryptophane). The proliferation-stimulating potencies nucleotides in (I) were negative18. In manometric of (I) and (II) were respectively 98-0 and 3-3 growth studies, both adenyl pyrophosphate and (I), but not units per ini.12, the solid contents 3-17 and 0-245 biotin or yeast adenylic acid, were found to elevate mgm. per ml. and the ultra-violet absorption markedly the oxygen uptake and respiratory quotient ([)/a:]log10t/0//*]) at 2600 A., characteristic of nucleo­ of growing or resting yeast cells9, simulating tides, 7 -0 and 1 -4. Thus, the grossly intact damaged phenomena frequently observed in damaged cells and cells released, as a result of increased permeability, tis s u e s 19. appreciable amounts of growth-stimulating sub­ Two conclusions appear of particular interest : stances and nucleotides. (1) adenine nucleotides (not hitherto regarded as growth factors) stim ulate the growth of yeast in well- supplemented media, and (2) the metabolic effects E f f e c t o f A d e n e n in e N u c l e o t id e s , K n o w n G r o w t h F a c t o r s , A m in o -A c id s a n d D a m a g e d -C e l l P r o d u c t s o n t h e G r o w t h o f of suspension fluids from damaged yeast cells are Y e a s t i n R e a d e r ' s M e d i u m . duplicated by combinations of adenine nucleotides and known growth factors. It remains to be deter­ 24 lir. yeast crop, mgm. (wot Addition to medium weight) per ml. (initial seeding, mined to what extent the release of known growth (concentrations in the cultures) 0 064 mgm. per ml.) factors and nucleotides by injured animal tissue cells plays a part in tissue metabolism and repair following R R + A R + A + B in ju r y . Supplements only (controls) 0 152 3-08 4-43 I wish to thank Dr. Fritz Lippmann, of the Harvard (I) Intercellular fluids from in­ jured cells, 0 *05 ml. per ml. 3-70 4-03 5-04 Medical School, for supplying several of the nucleo­ tides and for his kindly interest in the investigations. (II) Intercellular fluids from unin­ jured cells, 0 -05 ml. per ml. 0-803 3-00 4-31 J o h n R. Loofbourow. Adenosine, 5 X 10"5 molar 0-416 3-21 4-50 Muscle adenylic acid, 5 x 10-5 Departm ent of Biology, molar 0-488 3-44 4-65 Massachusetts Institute of Technology. Adenyl pyrophosphate, 5 x 10'5 J u n e 26. molar 0-309 3-32 4-85 Same, 2-5 x 10’4 molar 0-624 3-70 5-52 ■Carrel, A., J. Exp. Med., 33, 385 (1923); J . Amer. Med. Assoc., 82, 255 (1924). It = Reader’s medium20. 2 Hammett, F. S., Cold Sprinq Harbor Symposia Quant. Biol., 2, 78 A — following supplements (y per ml. of culture):: aneurin 0-25, pyrodoxin 0*50, biotin 0-000125, calcium pantothenate 0-125, (1934). riboflavin 0-5, choline 0-75, nicotinamide 2-5. 3 Fischer, A., Nature, 144, 112 (1039). B = following supplements (all 0-625 mgm. per ml. of culture): glutamic acid, asparagine, aspartic acid, leucine, arginine. ‘ Bonner, J., and English, T., jun., Science, 86, 352 (1937). 1 Calkins, G. L., Bullock, F. D., and Rohdenberg, G. L., ./. Infect. Dis., 10, 221 (1912). The similarity of the spectra of (I) to adenine14 in 8 Loofbourow, J. R., Dwyer, C. M., and Lane, M. M., Biochem. J., (a) selective absorption, (6) stability to p H change, 34, 432 (1940); Loofbourow, J. R., Dwyer, C. M., and Cronin, A. G., Biochem. J., 35, 003 (1941) ; Loofbourow, J. 11., Cook, and (c) lack of degradation by prolonged ultra-violet E. S., and Stimson, M. M., N atu re, 142, 573 (1938); Davidson, irradiation suggested an investigation of the prolifera­ J. N., Biochem. J., 34, 1537 (1940). tion-promoting effects of various adenine nucleotides. 7 Menkin, V., Cancer Research, 1, 548 (1941); Loofbourow, J. R., The absorption of (I) was equivalent to an adenine Cueto, A. A., Whalen, 1)., and Lane, M. M., N ature, 144, 939 molarity of 5 x 10"4. In corresponding concentra­ (1939). 8 Fardon, J. C., Carrol, M. J., and Ruddy, M. V., Studies Inst. D in tions, yeast nucleic acid and yeast adenylic acid Thomae, 1, 35 (1938). appeared to be inactive. Adenosine, muscle adenylic • Sizer, X. W., and Loofbourow, J. R., to be published. acid and adenyl pyrophosphate all stimulated growth, ‘“Menkin, V., J. Exp. Med.. 67, 129 (1938); “ Dynamics of inflamma­ the response with the last being most typical of that tion” (The Macmillan Company, N.Y., 1940). with (I) in the growth period up to 24 hours. In all 11 Loofbourow, J. R., Biocheii. J., in the press. instances, the activities of the nucleotides were much 12 One growth unit corresponds to an increased 24-hour yeast crop less than that of (I), indicating the presence of other in Reader’s medium of approximately 1,000 per cent as compared with the controls, under the standard assay conditions employed, growth factors in (I). Accordingly, the effects of (I), Loofbourow, J. R., Webb, A. M., Abramowitz, R. K., and Loof­ (II), adenosine, muscle adenylic acid and adenyl bourow, D. G., Biochem. J., in the press. pyrophosphate were tried in combination with known l3Wiesner, J., ‘‘Elementarstruktur” (Vienna, 1892): Haberlandt. G., Sitz, preuss. Akad. Wiss., 221 (1921); Beitr. Allgem. Botan., 2, 1 growth factors and amino acids. The combined supple­ (1921); Biol. Zentr., 2, 145 (1921). ments, growth factors and amino acids, masked the 14 Loofbourow, J. R., and Stimson, M. M., J . Chem. Soc., 844 (1940). stimulating effect of (II) but not of (I)15, as shown in 15 The supplements were computed to alford an excess of each factor the accompanying table, confirming similar results of from data of Williams, R. J., Eakin, R. E., and Snell, E. E., Cook16. Addition of adenosine, muscle adenylic acid J. Amer. Chem. Soc., 62, 1204 (1940). 18 Cook, E. S., personal communication and Studies Inst. Divi Thomae, or adenyl pyrophosphate to supplemented media gave in publication. increased growth in all instances. The higher con­ 17 Webb, A. M., to be published. centration of adenyl pyrophosphate plus growth 18 Loofbourow, J. R., Webb, A. M., and Abramowitz, l t . K., Nature, factors duplicated the effect of (I) in growth kinetics 149, 278 (1942). and total growth response, and the addition of adenyl 11 Fleischmann, W., Cold Spring Harbor Symposia Quant. Biol., 7, pyrophosphate at this concentration to media con­ 290 (1939). taining both supplements, growth factors and amino- 28 Reader, V., Biochem. J., 21, 901 (1927). Sexuality in Dugesia tigrina (syn. Planaria its training strengthens their social privileges. It is socially injurious, since it divorces this section of our maculata) people from the rest, from the life of the main part Individuals of the striped variety of Dugesia of the community, especially from all those engaged tigrina collected in the summer of 1935 in the pond in the productive processes and manual and technical behind the Episcopal Church, Falmouth, Mass., labour. Men brought up in the public school tradition have been maintained in the laboratory in finger are out of touch with modem social realities and bowls containing tap water and have been fed beef often incapable of grasping modern social problems. liver twice or three times a week. During their The prospect of endowing these schools with seven-year stay in the laboratory they have produced Treasury grants is usually linked with a proposal to egg capsules annually. admit into these schools a limited number of the In the spring of 1941 the egg capsules deposited by more gifted members of the poorer sections of society. the members of the original 1935 stock were isolated. This proposal is born as much from the financial The worms (Fl) hatching from them were raised under crisis of the public schools as from an awareness of the same conditions as the parents. During the current their social responsibilities. If it were adopted, the spring (1942), these animals (/'’,) produced cocoons main results would be : from which viable worms (F2) emerged. (а) a direct subsidy given by the taxpayer to the H ym an1 presents tiie theory that individuals of D. schools of the wealthy ; tigrina living in quiet water remain asexual and those (б) the psychological dislocation of the gifted poor subjected to a strong current or violent waves become boys, who would thus be in the position of poor sexual, producing many cocoons1. relation in the family of the rich ; Neither the 4 \ nor the planarians have ever (c) the stultification of the gifts of these hostages, been exposed to any strong current, and their parents since in this atmosphere they would lose contact and grandparents have lived a quiet, sheltered life with the life and problems of the mass of the people ; for six and seven years respectively. (d) the intellectual impoverishment of the State- The data are not compatible with the theory that aided secondary schools which would thus lose their ‘"moving water is the essential environmental factor most gifted pupils. in the development of sexuality in D. tigrina” . This However much the study of the natural and social hypothesis could only be tenable were we to concede sciences is cultivated in the public schools, the th at the i \ and J<\ animals become sexual because divorce between this type of education and life their ancestors at one time were exposed to moving cannot be overcome. Science under these social con­ water. This, the present available facts do not ditions tends to become an esoteric cult, isolated justify. E. D. G o l d s m i t h . from social purpose. If non-scientific subjects are Department of Biology, adapted to social ends, the public schools tend to College of the City of New York develop into institutions for the training of ‘leaders’, and Washington Square College, that is, into political academies for the firmer estab­ New York University. lishment of the dominance of a class. The type of 1 Hyman, L. H., Tram. Amer. Micro. Soc., 58, 264 (1939). social conscience thus engendered, and expressing itself in this sort of reform, is undemocratic and reactionary. Any botching and patching of the existing public school system will necessarily tend, whether or not The Public Schools in Great Britain by intent, to perpetuate present evils and inequality. T h e recent appointment of a Committee on Public It is true that some public schools possess, at present, Schools by the President of the Board of Education advantages from a technical-pedagogical point of has stimulated much discussion on the function of view over State-aided secondary schools. But this the public schools. The main object of this Committee is no reason for prolonging their existence in their is “to consider means whereby the association present form. Let us see their educational methods, between the Public Schools and the general educa­ their organization and their personnel applied to the tional system of the country could be developed and service of a wider community than the wealthy. extended”. The Committee’s terms of reference We do not ignore the fact that State-aided secon­ imply only a modification of the existing system. It is dary education stands in need of considerable reform. for this reason that we issue this statement raising the Much adjustment is needed in the matter of school whole question of the existence of the public schools. government, of curricula, of social status. Once the The constitutions of the schools included in the dichotomy in our secondary education is overcome a Public Schools Year Hook vary considerably. In concerted drive for reforms in these fields car be this document we use the term ‘public school’ to made, undistracted by considerations of social denote those schools which do not receive grants prestige and privilege. from the Treasury and which are maintained solely We call, therefore, for the full incorporation of the by fees and endowments. public schools into a unified, State-aided system of Britain is the only great industrial country where secondary education as a step towards democracy in wealth systematically buys a different type of educa­ our educational system and towards greater health tion for its offspring ; where education sets a different in our national life. aim for the wealthy than for those less well off. We thus preserve a system in striking contrast to those J . D. B e r n a l , P . G. H . B o s w e l l , S. B r o d e t s k y , of the U.S.A. and U.S.S.R., and of those smaller J. C h a d w i c k , W. E. L e G r o s C l a r k , F. A. E. C r e w , democracies such as the Scandinavian, to whose C. L o v a t t E v a n s , B. F a r r i n g t o n , C. B. F a w c e t t , social institutions we look with admiration. P . S a r g a n t F l o r e n c e , P . F . F r a n k l a n d , The system of public school education is undemo­ L a n c e l o t H o g b e n , J u l i a n H u x l e y , R. K. cratic. It segregates those children who, by in­ K e l s a l l , R . D. L a u r i e , J o s e p h N e e d h a m , heritance, proceed to leading positions in industry, R. P a s c a l , J . A. R y l e , F. S o d d y , H. G. S t e a d , politics, the civil services, the armed forces, and by G e o . T h o m s o n , F. E. W e i s s , F. W o o d -J o n e s . RESEARCH ITEMS with radial spikes and a new species with dorsiventral second spikes of sporangia. Good examples of Structure of Salivary Gland Chromosomes Cooksonia continue this type from the Downtonian

M. K o d a n i (J. Hered., 33, 115 ; 1942) has con­ to the Senni Beds, while Sporogonites, Sciadophyton tinued his experiments of treating salivary-gland and Taeniocrada are recorded for the first time from chromosomes with alkalis. By using urea-alkali mix­ British rocks. Prototaxites and Nematothallus occur tures he has been able to produce further changes along with the vascular plants, and Pachytheca is over and above the lamp-brush effect and thereby represented in several exposures. arrives at certain conclusions regarding the structure New Species of Fungi of the normal salivary gland chromosome. Three different series of transformations under treatment S e v e r a l descriptions of new species of fungi have were produced and these are shown to result from recently appeared (Trans. Brit. Mycol. Soc., 25, Pt. different modes of migration of part of the nucleic 3 ; June, 1942). T. Petch, in his continued studies acid from a peripheral position to the chromonemata on entomogenous fungi, finds new taxonomic units in the centre of the chromosome. The number of in Calonectria truncata, from leaf hoppers in the chromonemata per chromosome is definitely four ; West Indies, Hymenostilbe aphidis, also from the not polytene as stated by others earlier. Two chrom­ West Indies, Isaria (Beauveria) sphcerocephala from onemata are coiled intimately and in each disk ex­ lepidopterous larv® in Ceylon, and Gephalosporium pand laterally; the other two chromonemata coil subclavatum from similar larv® in Great Britain. also and form loops in the opposite direction in each Elizabeth G. Gray has described Phialea mucosa as disk. There appears to be a membrane to the chromo­ a new species. It appears to be the cause of blind some, but whether this is an artefact or a reality is spot disease of rye-grass, a malady originally studied not yet determined although the effect of nuclease by Neill and Hyde in 1939. treatment would suggest the presence of a membrane Gravity Measurements in Guatemala in the normal chromosome. A t the suggestion of E. G. Zies of the geo­ isolation and Collection of Salivary Gland Chromosomes physical laboratory of the Carnegie Institution of Washington who is working on the volcanoes Santa J. B. Buck and A. M. Melland (J. Hered., 33, 173 ; Maria and Santiaguito, F. E. Wright has made 1942) describe various methods for the preparation gravity measurements in the neighbourhood of the of salivary gland chromosomes for analysis by X-ray volcanoes (“Gravity Measurements fin Guatemala”, diffraction and electron-diffraction. Dissection of the by F. E. Wright. Geophysical Laboratory, Carnegie chromosomes from cells mounted in egg-albumen or Institution of Washington, 1941, No. 1049). It was water were feasible but the chromosomes underwent suggested that if a network of accurate gravity further changes in time. Therefore the chromosomes stations were to be established in the Santa Maria were first fixed in osmium tetroxide, acetic acid, or volcano region and the measurements were repeated formalin sufficiently long to make the nuclear mem­ at these stations periodically, changes in the values brane brittle enough to be cracked open. The chromo­ of gravity at the stations might serve to indicate somes were collected by a micro-pipette and trans­ the migration of the molten rock below the volcano ferred to collodion membrane and centrifuged to towards the surface. In establishing each gravity Pyrex glass capillaries. Preparations of 6,500 nuclei, station of the series its exact elevation was determined 1,000 nuclei and 800 nuclei respectively were photo­ in order that, if a change in the observed value of graphed by X-ray diffraction methods without gravity were obtained at a given station, it would success. Electron diffraction of mounted chromo­ be possible to ascertain if the change were due to somes gave one ring of 3-4 A., which is suggestive. uplift or downwarp of the surface at that point or to A block of chromosomes orientated in parallel fashion a shift in underlying rock masses and the upward containing 1,253 chromosomes and measuring 0-25 x movement of the molten mass. Magnetic and other 0-25 x 0 *05 mm. were photographed by Dr. W. T. measurements were made for comparison with the Astbury. X-ray diffraction results again gave sug­ gravity measurements. The gravity measurements gestive effects. The technique, when developed, will be were made with a Brown gravity pendulum loaned useful in future work. by the United States Coast and Geodetic Survey and a base station was occupied at Washington. Numerous Lower Devonian Plants difficulties were encountered, notably in connexion N e w and rich fossil localities discovered in the with the radio time signals on account of interference, Senni Beds of Monmouthshire and Breconshire have and the flexure of the basement floor of the observa­ yielded the most extensive and representative flora tory, but the following results were obtained, previous of late Lower Old Red Sandstone age in Britain results being given for comparison : (W. N . Croft and W. H. Lang, Phil. Trans. Roy. Soc., Station Observer Year Gravity Elevation B, 131, ; June, 1942). The specimens are represented gals. metres Guatemala City Pedro Sanchez 1935 977-973 1,494 by thin incrustations or by impressions, hence the Shell Company 1938 977*986 1,494 . information afforded is mostly relative to external F. E. Wright 1940 977-985 1,494 morphology. The remains of a spiny plant of Quezaltenango F. E. Wright 1940 977*781 2,384 Psilophyton princeps type have a hitherto unde­ scribed fructification in organic connexion with the Drifting Force on a Ship among Waves vegetative shoots. This fructification is quite unlike W h e n a ship is advancing through a train of waves Dawsonites of which typical examples also occur. it experiences an average steady resistance greater Numerous specimens of Gosslingia have shown that than that at the same speed in smooth water. Study the sporangia were not borne on special fertile of the wave pressure due to the reflexion or scattering branches as was originally supposed but on the of the ocean waves of the surface of the ship involves margins of the regular dorsiventral branch system. second-order terms in the hydrodynamical equations. Zosterophyllum is divided into two subgenera, one A solution is difficult but approximate calculations appear to show that the effect would account for a it heavily with bricks. A mechanical drive rather than small fraction only of the total effect. T. E. Havelock the hand drive is recommended for the camera; how­ continues his researches upon the subject by making ever skilful and careful the operator may be, a hand tentative calculations associating the effect directly drive cannot give the regularity of a machine. Instead with the oscillations of the ship (Phil. Mag., 33, 467 ; of starting exposures by using the computed time, it 1942). A steady average drifting force is obtained seems possible that better results would be obtained depending upon the phase differences between the by estimating the time from the size of the disap­ heaving and pitching motions and the periodic forces pearing crescent just before second contact. The and couples due to the wave motion. Although the success of the pit made for the instruments requiring available experimental data are not suitable for thermal protection suggests this method for future detailed comparison, the calculations give drifting eclipses, provided local conditions are suitable. forces of the same order of magnitude. Recent Changes in the Spectrum of y Cassiopeiae Stress Distributions in Solids of Revolution Miss E. M. P e a c h e y has described the changes in the T h e theoretical determination of stress distribu­ spectra of y Cassiopeise obtained on thirty-five plates tions in such complete solids of revolution as twisted taken at the University of London Observatory shafts of non-uniform diameter, axially symmetrical between July 8 and November 22, 1940 (Mon. Not. pressure vessels and in incomplete tores such as Roy. Astro. Soc., 102, 3, 1942). During this period, helical springs of small pitch, beams of large curva­ the hydrogen lines of the Balmer series varied from ture or hooks is extremely difficult by orthodox very sharp, strong absorptions with faint emission methods on account of the boundary conditions. borders to broad, fainter, diffuse absorption lines. Recent extensions of the relaxation method have Similar variations were observed, but to a much gone far to remove the difficulties, and lately trial smaller extent, with the lines of Helium I. A plate has shown them to be surmountable. Consequently, shows eighteen spectra which have been selected as the analysis has now acquired utility and has been typical and it includes two additional spectra taken given by R. V. Southwell (Proc. Boy. Soc., A, 180, during the summer of 1939. The latter show the 367 ; 1942) as a background to papers in course of transition from the emission-line stage to the sharp preparation. The ‘semi-indirect’ method of Saint absorption stage. A certain amount of detail which Venant is applied to determine directly, that is, with­ was visible on the original negative has been lost in out explicit reference to strains, the stress distribu­ reproducing the plate, but the changes described in tions in these solids. As the paper is intended as a the paper are easily seen. One particular feature prelude to approximate but general treatment of re­ shown on the plate is the general broadening of the laxation methods, only simple examples are given, lines and their subsequent narrowing on November but a -comparison is made with earlier solutions less 19 and 20 before they returned to normal on Novem­ suited to a ‘relaxation’ approach. ber 22. A summary of the observed changes in the Thermal Vibrations and Scattering of X-Rays spectrum is given and it is suggested that more plates, obtained with an instrument of higher dispersion, M. B o k n continues his studies of the subject in a should be taken when rapid changes in the star are third paper (Proc. Roy. Soc., A, 140, 397 ; 1942). noticed. C. V. Raman’s explanation of the diffuse scattering is compared with the ‘thermal’ theory which in its Sunspots during 1938 revised forms satisfies the demand of a theory based A p a p e r on the mean areas and heliographic on quantum principles. The relationships of the latitudes of sunspots during 1938 has been communi­ dynamical matrix, describing the mechanical pro­ cated by the Astronomer Royal to Mon. Not. Roy. perties of the lattice and the scattering matrix, de­ Astro. Soc., 102, 3, 1942, and is a continuation scribing the scattering power are discussed, together of earlier results. (Mon. Not., 100, 495, 1940). with the influence of the ordinary Raman effect on The measurements of photographs taken at the the scattering. Royal Observatories of Greenwich and the Cape and Spectrographic Observations at the Total Eclipse of at the Kodaikanal Observatory, India, were con­ October I, 1940 ducted at Greenwich, and the results are given in R . O. R e d m a n has prepared two papers on this four tables. The years 1937-38 constitute a notable subject (Mon. Not. Roy. Astro. Soc., 102, 3 ,- 1942), sunspot maximum compared with the outstanding the first of which, “Instrument and Observational peak of 1870 (Kew photographs) and those of 1837, Procedure”, is summarized in the present note. The 1788 and 1778 (Wolf’s numbers). In 1938 the second paper is only the first of a series dealing with southern hemisphere showed greater activity in con­ spectrographic observations. The author was with trast w ith 1937, when the northern hemisphere was the eclipse party at Calvinia. It is interesting to more active. During 1938 there were th irty spots notice that a correction was made to the tabular which were not less than 500 millionths of the sun’s longitude of the moon of 0-8" instead of the Nautical hemisphere in mean area, and of these, nine were of Almanac value 2" and, in spite of this better value, mean area greater than 1,000 millionths. One of totality came more than 3 seconds earlier than the these great groups had a mean area of 2,955 millionths predicted time. A number of suggestions and also and was the second largest group ever recorded at some criticisms are offered for the advantage of those Greenwich. The latitudes for individual spots ranged who may make observations with similar, though from 0-7° to 45-6°, and the mean latitude of all spots improved apparatus, at eclipses in the future. Among weighted according to area was 14-8°. The mean these may be noted the suggestion that the ccelostat latitude thus continues the equatorward progression drive should be rated to follow the moon. The of the mean spot belt in the two hemispheres during ccelostat and concave mirror mountings should the eleven-year cycle. The above figures are based be mounted substantially ; it was found that the upon two one-day spots, but the range was found to mount for the concave mirror at Cavinia vibrated be from 1-8° to 42-1° for spots of duration not less even in a gentle breeze, and it was necessary to load than two days. THE LEAGUE OF NATIONS ditions. The Weekly Epidemiological Record has appeared regularly at Geneva without any inter­ REPORT on the work of the League of Nations, ruption and an annual Epidemiological Report was A 1941-42, which has been submitted by the distributed at the end of 1941. The standardization Acting Secretary-General, well indicates the valuable of sera and of vitamins has continued, and results of contribution which the League should be able to the latest research conducted under the Commission make to the solution of problems of reconstruction, were published in 1941 in the Bulletin of the Health European relief, and the like, apart altogether from Organisation. The Health Section is also endeavour­ whatever value its organization and machinery may ing to ascertain the effect of food rationing on the possess as a starting point for a fresh attempt to general level of health of European populations, and organize peace and to plan international co-operation. has supplied information on numerous health ques­ Dealing first with economic, financial and transit tions such as the effect of the War on the health questions, the report notes that the League’s World situation, typhus, tuberculosis, feeding and nutrition, Economic Survey, its Statistical Year-book and the etc.; reference is made to the future opportunities Monthly Bulletin of Statistics have been maintained, for action which the field of nutrition appears to and while the headquarters a t Geneva have specialized offer the Health Organisation. on European developments, the part of the Economic, Activities in regard to the control of the drug Financial and Transit Department sent on mission traffic have been essentially maintained, and the to Princeton follows the course of events in the rest Permanent Control Opium Board continues to watch of the world. In addition to the three pivotal pub­ the international trade in narcotic drugs on the basis lications already mentioned, the Secretary-Gene of statistical information supplied by Governments. proposes to publish this year the statistical part of The Child Welfare Information Centre has been the work previously published in two volumes under maintained and intellectual co-operation has con­ the title “Money and Banking”. tinued in the United States, where the national com­ In regard to post-war economic problems, the pro­ mittees of that continent held their second conference gramme visualized for 1942 is guided by three prin­ at Havana in November 1941. The programme in­ ciples. Since the future must be built on the past, it cluded the examination of the basic principles upon is essential before planning and projecting that build­ which intellectual co-operation depends : improve­ ing to ascertain the causes of success or failure in the ment of copyright regulations ; removal of obstacles recent past, and to learn and apply the lessons which to cultural and intellectual exchange, such as high may be deduced from the past. Secondly, such duties on books, excessive postal rates. International evidence must be supported by an adequate basis assistance to refugees is being continued on the lines of fact, the relevant information being collated and laid down by the Assembly in September 1938, and analysed to assist those responsible for the formula­ brief reference is made to such matters as mandates, tion of policy to frame their own judgment on them. slavery, the protection of minorities and the registra­ Thirdly, the care of the social and economic issues tion of treaties where the League’s administrative of the future is likely to be the problem of social work has been interrupted or restricted by the War. security, and the means by which control of the two The report includes an analysis of the League’s groups of dynamic forces at present discernible in budget and of the reduction in the staff of the modern society may be rendered effective should secretariat, but gives an encouraging and indeed sur­ therefore constitute the central thread of all con­ prising picture of the maintenance of economic, structive thinking for the future, and all future social and humanitarian activity and of the con­ policies must be considered in the light of their prob­ servation of reserves in readiness for the resumption able effect on economic stability, on demographic of co-operation and the handling of reconstruction conditions, and on social security. The programme problems. includes commercial studies, one of which, “Europe’s Trade”, has already been published, studies on raw materials such as obstructions to free access, control schemes, raw-material shortages and surpluses at the end of the War of 1914-18 and on proposals to secure MAN-POWER IN THE NATIONAL equal conditions of supply or prevent violent fluctua­ FIRE SERVICE tions in price, as well as on the whole experience of relief and reconstruction. In regard to agriculture, T seems clear, from the thirteenth report of the a careful study is being made of current agricultural Select Committee on National Expenditure, deal­ developments in war areas and elsewhere. Inter­ ingI with the National Fire Service, that the adminis­ national currency problems, economic depressions tration of the Service is already under close scrutiny and social security and demographic questions are from within, and that active steps are already being also receiving attention, as well as transport in rela­ taken to discover ways and means of simplifying tion to post-war relief and reconstruction and the the administration and reducing the staff. Centraliza­ preparatory examination of the future international tion of the administration at area headquarters re­ organization of transport. A full programme of quires speeding up in urban areas, while in rural studies on European demographic problems is out­ areas decentralization is the recommended policy, lined in the report. with a more direct connexion between region and In regard to social and humanitarian questions, division. Amalgamation of some of the administra­ the Secretary-GeneraPs report describes the way in tive posts, such as establishments and stores, appears which the Health Section continues to deal with to be possible, and experience in Scotland should questions of epidemic disease. The service of Epi­ provide a useful guide as to some of the possibilities demiological Intelligence and Public Health Statistics in this direction. has continued, with interruptions, and Singapore The question of man-power is one of the major Bureau has now been re-opened in Australia, where it problems considered by the report. Partly it is is carrying on within the limits imposed by war con­ approached from the point of view of utilizing in some effective way the time of the men who are standing by, and the report recommends that the CONTACT RESISTANCE fullest use should be made of the skilled men in the r T 'vHE effects of contact resistance on temperature Service by the setting up of workshops for the repair A rise in switches are examined by R. W. J. of motor-vehicles and also for the repair of uniforms. Cockram in the Electrical Review of August 21. A While the report recommends that the practice of factor complicating the control of electric circuits is allowing men on duty to do some industrial work at the contact resistance set up between two mating their stations should be encouraged and expanded surfaces of metal which at times have to be separated at once to the utmost extent possible without inter­ in order to break continuity of supply. The two main fering with their routine duties and training, the methods of decreasing contact resistance—excluding attitude of the Select Committee on this question is the use of special contact tips—are to increase the similar to that of Mr. Morrison as indicated in his contact area and to increase the contact pressure. speech on July 30 ; neither seems to realize the very Contact pressure can be increased only to a certain serious problem of man-power which is involved and limit, beyond which it results in a welding-in of is likely to increase in gravity. The Committee’s contacts. Large contact surfaces are uneconomical ; objection to the 24-24 hour system that such a prac­ they are, in fact, made as small as possible con­ tice may not be good for the Service, as a man may sistent with a contact pressure low enough to preclude very easily become more interested in his civilian welding-in. job, can scarcely be taken seriously in the present Knife type contacts depend mainly on large situation. If a uniform system of hours is to be contact-surface area rather than high mating surface adopted for the whole country, as the Committee pressures to maintain low resistance values. Unless recommends, the effects of the 24-24 hours system enclosed they are operated only under no-load con­ with the men directed to eight-hour factory shifts ditions, and should not be worked in excess of 500 on their days off during lulls, as is being attempted amp./sq. in. Point butt-type contacts mainly find in the north-west of England, should be examined. application on instrument-control switches, control - Somewhat surprisingly, the other aspect of this circuit contacts or interlocks on contactor gear. question of hours and of the importance of alternative Rarely rated above 5 amp. at 440 volts, their contacts occupation is rather overlooked by the Committee. are usually of silver and take the form of portions of The report shows little appreciation of the real dangers spheres, two breaks in series being employed. A to efficiency which arise from keeping men too long slight ‘wiping’ action takes place which assists oxide confined to their stations, and insufficient attention removal. Line butt-type contacts are also chiefly is given to welfare work in the National Fire Service. associated with contactor apparatus. In these, The Committee in fact scarcely appears to realize heavy pressures are applied, generally to the main that the troubles of the National Fire Service spring poles of contactors up to 150 amp. with spring chiefly from long periods of inaction and the failure pressures of 8-10 lb./sq. in. Replaceable contact tips to divert or occupy its members ; indeed it suggests are used, and a degree of wiping is provided. Surface that welfare should be primarily the responsibility of type contacts call for complete mating of the contact the various commanding officers, assisted by the surfaces ; each moving contact is divided into four establishment officer, and it is recommended that segments, each segment being acted upon by two welfare officers should not be specially appointed. springs. Taper-butt surfaces are employed for the Probably officers who can find leisure occupation for control of heavy currents, as in circuit breakers and the men and watch over their conditions of living, similar equipment. eating and sleeping are the greatest need of the In all the forms of contacts cited, pressure is National Fire Service to-day. Moreover, although a applied to the mating surfaces. Some small degree wide view of welfare not limited to sporting activities of spot welding may be permitted while the wiping is taken, nothing is said on the question of educational action is sufficient to break it ; it is, however, best service. That has still to receive o.ficial encourage­ prevented. Burning and pitting was at one time ment ; indeed in London, where it was commenced considered to take place during the breaking of by the men, it was for long hindered rather than circuits but it is now mainly attributed to imperfect helped, and other regions have nothing of the kind. mating over long periods in the engaged position, the Nevertheless, the need of the Fire Service for educa­ resulting oxidation causing further heating. Silver tional service is just as great as that of the Army, contacts are accordingly used, giving a greater where its value has long been recognized. working life since silver oxide is a comparatively There aro few ways in which the local authorities good conductor. could better display their interest in the fire service now that it has been nationalized. The health and cultural welfare of this body of men, their own citizens, MAGNETIC FLUXMETER though now serving in a national force, gives a great opportunity. They could do much to support educa­ EASUREMENT of magnetic field strength due tional schemes, even if they cannot assist in their M to current in a coil is usually made by changing initiation, and to demand and maintain good living the current and observing the voltage induced in a conditions. Whatever advantages there may have search coil or in the coil itself. This voltage is pro­ been in a local service with its fuller knowledge of portional to the rate at which the magnetic flux local conditions could at least be utilized in welfare varies and it fluctuates in magnitude and direction, work, with benefit in efficiency and morale. if the field pulsates or alternates. For rapid flux To bring to concert pitch, adequately but not over­ alternations a galvanometer will show no deflexion, staffed, such a force as the National Fire Service, and but a steady reading can be obtained if the galvano­ to maintain that efficiency over prolonged periods of meter connexions are reversed as the induced current inactivity, demand inspired leadership alive to the reverses. The deflexion is then a measure of the human issues as well as to the technical problems magnetic field under observation. A practical applica­ involved. tion of this method is the measurement of voltage Scottish Society for Research in Plant-Breeding. Report (abridged) induced in a relay by the operation of a neighbouring by the Directors and Report by the Director of Research to the Annual relay. General Meeting, 16th July 1942. Pp. 34. (Edinburgh : Scottish A fluxmeter working on these principles has been Society for Research in Plant-Breeding.) [89 developed in the Bell Laboratories and is described Amgueddfa Genedlaethol Cymru: National Museum of Wales. Plant Illustration from Woodcut to Process Block: Handbook to a by E. L. Norton (Bell Lab. Rec., 20, No. 10; June, Temporary Exhibition, based on the Collection in the Department 1942). I t has a pulse generating device operating of Botany, July-December 1942. By A. E. Wade. Pp. 32. (Cardiff : National Museum of Wales.) 3d. [89 high-speed relays which reverse simultaneously the Medical Research Council: Industrial Health Research Board. current producing the flux and the meter connexions. Emergency Report No. 3 : The Personal Factor in Accidents. Pp. 20. Pulse rates of 30, 15, 7 -5 and 3-75 per sec. are obtained (London : H.M. Stationery Office.) 4d. net. [89 from gas tube discharges as submultiples of 60-cycle Economic Proceedings of the Royal Dublin Society. Vol. 3, No. 9 • Notes on some Lepidopterous Pests on Fruit Trees, and their Parasites, alternating current. The measuring circuit includes in Ireland during 1941. By Dr. Bryan P. Beirne. Pp. 107-118. (Dublin: a bridge which is used when flux is measured by the Hodges, Figgis and Co., L td .; London: Williams and Norgate, Ltd.), voltage induced in the coil itself. Switching is so 1*. [89 Imperial Bureau of Soil Science. Technical Communication No. 41: arranged that, when not pulsing, the bridge may be The Take-All Disease of Cereals. By S. D. Garrett. Pp. ili+40. balanced using the indicating meter as a galvano­ (Harpenden : Imperial Bureau of Soil Science.) 2«. 6d. [89 meter. A loss pad is incorporated enabling the meter Scientific Proceedings of the Royal Dublin Society. Vol. 22 (N.S.)’ No. 49 : Salmon of the River Erne—Results of the Examination of a to read one third or one tenth of the actual Small Collection of Scales and Data. By Arthur E. J. Went. Pp. current. This apparatus gives readings more con­ 471-480. (Dublin : Hodges, Figgis and Co., L td .; London : Williams veniently and accurately than previous magnetic and Norgate, Ltd.) 1«. [89 Civil Service Reform : the Interim Report of the Sub-Committee fluxmeter readings usually made with a ballistic on the Reform of the Civil Service appointed by the Industrial and galvanometer. In addition, it has the added advantage Social Reconstruction Committee of the Liberal Party. Pp. 16. of being suitable for adaption to a portable con­ (London: Liberal Publication Department.) 3d. [99 Infant and Maternal Mortality in relation to Size of Family and struction. Rapidity of Breeding : a Study in Human Responsibility. By C. M. Burns. Pp. viii-f- 247. (Newcastle-upon-Tyne: King’s College Medical School.) 5 8. [109 Other Countries Bulletin of the American Museum of Natural History. Vol. 79. FORTHCOMING EVENTS Art. 7 : Results of the Archbold Expeditions, No. 43 : Birds of the Tuesday, September 22 1938-1939 New Guinea Expedition. By A. L. Rand. Pp. 425-516. Vol. 79, Art. 8 : Results of the Archbold Expeditions, No. 44 : Some I n s t it u t e of Physics (at the Royal Institution, Albemarle Street, Notes on Bird Behavior. By A. L. Rand. Pp. 517-524. (New York : London, W.l), at 11 a.m.—Discussion on “The Determination of American Museum of Natural History.) [278 Equilibrium Diagrams by X-Ray Methods”. (Opening speakers: Proceedings of the United States National Museum. Vol. 92, No. Dr. A. J. Bradley, F.R.S., Dr. W. Hume-Rothery, F.R.S., Dr. M. L. V. 3145: Notes on Beetles related to Phyllophaga Harris, with Descrip­ Gayler, Prof. E. A. Owen.) tions of New Genera and Subgenera. By Lawrence W. Saylor. Pp. 157-165+plate 17. Vol. 92, No. 3146 : Descriptions of the Larvae of some West Indian Melolonthine Beetles and a Key to the Known Wednesday, September 23 Larvae of the Tribe. By Adam G. Böving. Pp. 167-176 4-plates 18-19. B r it is h S o c ie t y f o r I nternational B ibliography (at the Science (Washington, D.C.: Government Printing Office.) [288 Museum, Exhibition Road, South Kensington, London, S.W.7), at Bericht über das Geobotanische Forschungsinstitut ltübel in Zürich 2.15 p.m.—Presidential Address. Mr. H. Rottenburg : “Publishers für das Jahr 1941. Von E. Rübel und W. Lüdi. Pp. 37+2 plates. and the Universal Decimal Classification*’. (Zürich: Geobotanische Forschungsinstitut Rübel.) [288 Agriculture and Animal Husbandry in India, 1938-39. Pp. v + 422 + 10 plates. (Delhi: Manager of Publications.) 6 rupees; Saturday, September 26 6«. 9d. [89 S o c ie t y o f C h e m ic a l I n d u s t r y ( J o in t M e e t i n g o f t h e M a n ­ Consejo Superior de Investigaciones Cientiflcas : Instituto Nacional c h e s t e r S e c t io n a n d t h e F o o d G r o u p ) (in the Reynolds Hall, College de Geoffsica, No. 3 (Memorias del Observatorio del Ebro, 8): Con­ of Technology, Manchester), at 2.30 p.m.—Dr. L. H. Lampitt: “The tribution al estudio general del problema de la rcpeticiön de los Preservation of Foodstuffs”. eclipses. Por Dr. Josö M* Torroja Menöndez. Pp. 98. (Tortosa: Libreria de Alguerö y Baiges.) [89 Proceedings of the California Academy of Sciences, Fourth Series. Vol. 23, No. 31: Notes on a Collection of Reptiles and Amphibians from Guatemala, 2 : Lizards. By Joseph R. Slevin. Pp. 453-462. Vol. 23, No. 32: Notes on a Collection of Reptiles from Boquete, Panama, with the Description of a New Species of Hydroi orphus. APPOINTMENTS VACANT By Joseph R. Slevin. Pp. 463-480+plates 39-42. (San Francisco, A pplications are invited for the following appointments on or Calif.: California Academy of Sciences.) [89 before the dates m entioned: Indian Forest Bulletin No. I l l (Utilisation, New Series): Cheap and Simple Types of Tanks for the Treatment of Timberby the Dipping, D r a in a g e E n g in e e r to the Hampshire Rivers Catchment Board—■ Steeping or Open Tank Process. By Dr. D. Narayanamurti. Pp. The Clerk to the Board, The Castle, Winchester (September 28). iii+3+6 plates. (Delhi: Manager of Publications.) 6 annas; 7d. [89 D ir e c t o r o f t h e C h e m ic a l R e s e a r c h L a b o r a t o r y , T e d d in g t o n —T he Secretary, Central Register (Ref. F690), Ministry of Labour Publications of the Dominion Observatory, Ottawa. Vol. 13: Bibliography of Seismology, No. 11: Items 5280-5356, January to and National Service, Sardinia Street, Kingsway. London, W.C.2 June, 1942. By Ernest A. Hodgson. Pp. 189-200. (Ottawa : King’s (September 30). Printer.) 25 cents. [89 T e a c h e r o f E l e c t r ic a l E n g in e e r in g —The Principal, Wolverton Canada : Department of Mines and Resources : Mines and Geology Technical College, Wolverton, Bucks. (October 3). Branch, Geological Survey. Paper 42-1: Preliminary Map, Manson- L e c t u r e r i n P h y s io l o g y —The Principal, Liverpool Physical ville, Quebec. By J. W. Ambrose. 10 cents. Paper 42-2 : Second Training College, Barkhill Road, Liverpool 17. Preliminary Map, Manson Creek, British Columbia. By A. H. Lang. 10 cents. Paper 42-3 : Marble Mountain Map-Area, Alberta (Sum­ G r a d u a t e L e c t u r e r with good Honours or higher qualifications in mary Account). By H.H. Beach. Pp. 15+map. 10 cents. Paper 42 4: M a t h e m a t ic s —The Principal, Neath Mining and Technical Institute, Brock River Map-Area, Abitibi and Mistassini Territories, Quebec Neath, Glamorgan. (Summary Account). By E. D. Kindle. Pp. 7+map. 10cents. Paper 42-5 : Preliminary Map, Cypress Lake, Saskatchewan. By G. M. Furnival. 10 cents. Paper 42-6 ; Preliminary Map, Princeton, British Columbia. By H. M. A. Rice. 10 cents. Paper 42-8: Preliminary Map, Bassano, Alberta. By J. S. Stewart. 10 cents. Paper 42-10 : Preliminary Map,Eastmain, Quebec. By G. Shaw. 10 cents. (Ottawa: REPORTS and other PUBLICATIONS King’s Printer.) [89 (not included in the monthly Books Supplement) Catalogues ST’R Electronic Controls. (AH-243.) Pp. 4. (London : L.A. Steiner). Great Britain and Ireland A Supplement of Scientific Books. (No. 17c, 1942.) Pp. 12. Ministry of Health. First and Second Interim Reports of the (Cambridge : W. Heffer and Sons, Ltd.) Medical Personnel (Priority) Committee. Pp. 12. (London: H.M. Gestyl Organon: Gonadotrophin of Pregnant Mare Serum. Pp. 6* Stationery Office.) 2d. net. [89 (London: Organon Laboratories, Ltd.) Reports of the Progress of Applied Chemistry. Vol. 26, 1941. Pp. General Catalogue. (Catalogue No. 663.) Pp. 74. (London: Francis 545. (London : Society of Chemical Industry.) [89 Edwards, Ltd.) BOHB.D.H. Laboratory Chemicals are used as the standard equipment in analytical labora­ tories in which important and responsible work is undertaken.

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