744 NATURE November 6, 1948 Vol. 162

INTERNATIONAL UNION OF GEODESY AND GEOPHYSICS

HE Eighth General Assembly of the Inter• The hospitality of the municipality of Bergen formed T national Union of Geodesy and Geophysics, and a fitting close to a memorable occasion. of its seven constituent associations, was held at Association of Geodesy. The work of the Association Oslo during August 19­28. The opening assembly, of Geodesy was distributed over five sections. In held in the large hall ('Aula') of the University of the Section on Triangulation there was much dis• Oslo, was attended by the King of Norway and the cussion on methods of measuring long distances, Crown Prince. The Government of Norway and the including triangulation between non­intervisible municipality and the ·University of Oslo extended ground stations by radar and by the observation of the most generous hospitality to the Union. A large flares dropped from aircra.ft. Consideration was also amount of careful preparation had been done by given to the proposal to extend the Central European the Norwegian Organising Committee under the Net to Western Europe. In the Section on Geodetic chairmanship of Prof. H. Solberg, secretary of the Levelling, deliberations were mainly devoted to Academy of Science and Letters. refinements in the practice and theory of geodetic Owing to the state of health of the president, Prof. levelling and to the methods of research into those Helland­Hausen, of Norway, the duties of president problems of tectonics on which levelling is capable of were carried out by the senior vice­president, Prof. throwing light. The Section on Geodetic Astronomy N. E. NOrlund, of Denmark. The general secretary gave consideration to co­operation with the Inter• of the Union is Dr. J. M. Stagg, of the British Meteor• national Unions of Astronomy and of Telecom• ological Office. The Council of the Union consists of munications. An interesting and important report one delegate from each country ; the British member on the activities of the Royal Observatory was of the Council was Prof. J. Proudman. There were received from the Astronomer Royal. more than five hundred delegates and guests from In the Section on Gravimetry it was noted that about forty countries. The largest party was the since 1939 the rapid development of static gravi• British, numbering nearly eighty, of which about half meters has brought them into general use, not only were delegates appointed by the Royal Society ; but for geodetic purposes but more especially for geo• the party from the United States exceeded seventy. logical prospecting by oil companies. As a result, This was the first ordinary General Assembly since the the quantity of gravity material accumulat,ing in War; a small, purely administrative Assembly had some areas is more than can be conveniently handled been held at Cambridge in 1946, and this enabled the in geodetic work. It was decided that the Association Oslo delegates to devote the maximum amount of should set up a Gravity Bureau. In the Section on time to scientific discussion. Evening lectures by the Geoid, attention was given to deviations of the Dr. M. A. Tuve, of and by Dr. S. vertical, to geoidal rise and deflexions, and to the Thorarinsson, of Iceland, the latter showing a remark• application of methods of differential geometry to able colour film on the recent eruption of Mt. Hekla, geoidal determination. There was a heated discussion were much appreciated. Prof. Vening Meinesz, of on the 'co­geoid­fictitious level surface of the earth' Holland, was elected president of the Union for the after the removal of effects of compensated topo• period 1948­51. An invitation from Belgium to hold graphy. the next General Assembly at Brussels in 1951 Was Both the president of the Association, Mr. W. D. gratefully accepted. Lambert, of Washington, and its secretary, Prof. P. The Union expressed its gratitude for the very rardi, of Paris, were re­elected. considerable financial assistance which it has received Association of Seismology. This Association bene• from Unesco. The major part of this has consisted fited from the fact that a preliminary meeting had of grants in aid of the permanent scientific services been held at Strasbourg in 1947. Without world­wide which are sponsored by the Union; the largest co­operation the progress of s ismology would have individual grant for 1948, £3,000, is in aid of the been extremely slow. A notable example of such International Seismological Summary, $e staff of co­operation is the International Seismological Sum• which is housed at Kew Observatory. But many of mary, for which the Association is responsible; the officers of the Union received Unesco grants in significant measures for increasing the usefulness of aid of their travelling expenses to and from Oslo. the Summary were agreed upon at Oslo. A special A very valuable feature of the Assembly was the session of the Association wfl,s devoted to recent excursions, and it Was on these that the warm• researches on the seismicity of the earth. One of the hearted hospitality of the Norwegians reached its sessions was devoted to the study of the seismic height. It is the common experience of those attend• results of the large explosions at H eligoland, Burton• ing international conferences that the personal on­Trent, Haslach and Soltau, and to the results of contacts made on such excursions are, even from the seismic prospecting in France, Spain and the United point of view of the advancement of science, the States. most valuable part of the whole proceedings. Most The president, Dr. R. Stoneley, of Cambridge, and delegates and guests accepted invitations to visit the the secretary, Prof. J. Rothe, of Strasbourg, were district around Lillehammer on August 22. After the re­elected. Assembly, forty delegates enjoyed a most entertaining Association of Meteorology. In his presidential and instructive visit to the hydro­electric works at address to the Association of Meteorology, Prof. S. Rjukan as the guests of Norsk Hydro. The meteor• Chapman made a strong case for an International ologists and oceanographers took part in excursions Meteorological Research Organisation to link together which met far up the Sogne Fjord, and from this the various meteorological research bodies throughout point they were conveyed to Bergen in five research the world, and to serve as a clearing house for ideas. vessels, four of them Norwegian and one Scottish. A strong impression was created by the discussion

©1948 Nature Publishing Group No. 4123 November 6, 1948 NATURE 745 on rain­making by artificial means. Other important moon. Contributions included reports dealing with contributions included the following : a theory of volcanic activity during the past decade, in Japan, selective unstable waves in an atmosphere described Kamchatka, the East Indian archipelago, Guatemala, by the boundaries of the tropopause and the earth's the West Indies, Africa, Iceland, Etna., Vesuvius, surface, a subject which is connected with the and elsewhere. Few vulcanologists attended the formation of short­lived cyclones ; fundamental meeting, which is largely to be ascribed to the problems in the study of radiation ; the density of coincidence in time of the International Geological the high atmosphere as determined by the motion of Congress in London. meteorites ; the need for more observations of water Two new objects were brought forward, and to these vapour and of helium in the high atmosphere; particular attention was given. A commission was antarctic meteorology; jet streams; and the possi­ set up under the chairmanship of Prof. L. Glangea.ud bilities of statistical forecasting. Mr. A. W. Brewer for the purpose of studying the extinct volcanoes of exhibited an automatically controlled frost­point the world with special reference to the relations hygrometer, based on the design which he and Dr. between geological time and the changing com­ Dobson had evolved, and gave an impressive account position of the magmas concerned. A long­standing of the water vapour content above the tropopause. policy of the Association, for which funds have been Prof. Byers showed a film exhibiting in slow motion accumulated over a number of years, is the pub­ the records of radar reflexion from rain during lication of a catalogue of the active volcanoes of the thunderstorms over Florida. world, and a conference was held on the scope of the Prof. J. Bjerknes resigned the office of secretary catalogue, and its compilation and publication. and was elected president ; Prof. J. van Mieghem Prof. B. G. Escher, of Holland, was elected president, was elected secretary. and Prof. F. Signore, of Italy, was re­elected as Association of Terrestrial Magnetism and Electricity. secretary. '!'he discussions of this Association included the fol­ Association of Hydrology. The work of the Asso­ lowing subjects : the influence of solar activity on ciation of Hydrology was spread among the four terrestrial magnetism; air­borne magnetic surveys commissions : limnology, potamology, underground carried out in the United States and in Britain, water, snow and glaciers. The Limnology Com­ which show great promise for the near future ; the mission dealt with the balance­sheet of a lake, with origin of the earth's magnetism; diurnal variation statistics of lake­level and with the movement of of the horizontal force near the magnetic equator ; water in lakes ; the Potamology Commission with detection of rapidly moving ionic 'clouds', observed evaporation, with precipitation­recording methods, during ionospheric storms ; and the use of V2 rockets and with transport of solid material in Nature and for the exploration of the upper atmosphere. in the laboratory; and the Underground Water Owing to the absence of the president, Dr. J. A. Commission with infiltration, with variations of level Fleming, of Washington, the chair at the early in springs, and with hot springs in general. meetings was taken by Prof. J . Coulomb, of Paris ; The Commission on Snow and Glaciers, in addition Prof. S. Chapman, of Oxford, was then elected to the set themes, dealt, inter alia, with suggested president, and presided at the later meetings. '!'he classifications of snow, and with the alternative secretary, Dr. J. W. Joyce, of Washington, was methods of observation and reporting which are now re­elected. in use in the United States and Switzerland. The Association of Physical Oceanography. A change of report on glacier variations was the first to be made emphasis as compared with those at earlier Assem­ by the new permanent committee which was estab­ blies was shown in the meetings of the Association of lished at Washington in 1939 to carry on the work Physical Oceanography. Previously, most attention of the long­established Commission Internationale was given to the distribution of temperature and des Glaciers. '!'he statistical data up to now have salinity in the oceans and to the deductions regarding dealt solely with the changes of position of the water­movements, etc., which could be drawn from glacier snouts; but in future it is planned to include such distributions. On this occasion, most attention three­dimensional surveys of selected glaciers. There was given to observations of oscillations in the sea, was an exhibition of glaciological films. It was including surface­waves, turbulence and storm­ decided to reduce the number of commissions to surges. The change reflects a result of the War, three: underground water, lakes and rivers, snow which prevented ocean­going expeditions and turned and ice. attention to problems associated with the landing of The Association met linder the chairmanship of troops on beaches. For the first time, British Prof. G. Slettenmark, of Sweden, who had been oceanographers took a prominent part in the present­ appointed acting president after the death in 1947 ation of papers. of Prof. 0. Lutschg, of Switzerland. The secretary, Most of the standing scientific committees of the Prof. F. Dienert, of France, died shortly afterwards, Association, including those on mean sea­level, ocean and his place was filled by Prof. A. M. Vibert, of bottom, weather ships and technical handbook, were France, as acting secretary. At the close of the reappointed, while a new one on bibliography was Assembly, Mr. Merrill Bernhard, ofthe United States, set up. The president, Prof. H. U. Sverdrup, of Oslo, was appointed president, and Prof. L. Tison, of was re­elected. Prof. J. Proudman, of Liverpool, Belgium, was appointed secretary. resigned the secretaryship, and Prof. H. Mosby, of A joint meeting of the Associations of Seismology, Bergen, was appointed to succeed him. Meteorology and Physical Oceanography was devoted Association of Vulcanology. In the absence of the almost entirely to thirteen papers on microseisms, president, Prof. Michel­Levy, of Paris, owing to ill­ recent developments in this subject showing how health, the Association of Vulcanology met under the profitable has been co­operation between workers in chairmanship of one of the vice­presidents, Prof. the different sciences. The Union Committee on B. G. Escher, of Leyden. His address was on the and Struct'?'e was replaced by asymmetrical shape of the earth's surface and its a J omt Inter­Assocratwn Commrttee on the Physics effect upon the volcanism of the earth and the of the Earth's Interior. J. PRouDIII.AN

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