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Scientific Instrument Society Bulletin of the Scientific Instrument Society No. 46 September 1995 Bulletin of the Scientific Instrument Society LSSN0956-8271 For Table of Contents, see inside back cover President Gerard Turner Honorary Committee Howard Dawes, Chairman Stuart Talbot, Secretary John Didcock, Treasurer Willem Hackmann, Editor Michael Cowham, Ad~wtising Manager Trevor Waterman, Meetings Secretary Gloria Clifton Jane [nsley Arthur Middleton Alan Morton Membership and Administrative Matters The Executive Officer (Wing Cmdr. Geoffnm] Bennett) 31 High Street Stanford in the Vale Faringdon Tel: 01367 710223 Oxon SN7 8LH Fax: 01367 718963 See inside back cover for information on membership Editorial Matters Dr. Willem D. Hackmann Museum of the History of Science Old Ashmolean Building Tel: 01865 277282 (office) Broad Street Fax: 01865 277288 Oxford OXI 3AZ Tel: 01865 54058 (home) Advertising Mr Michael Cowham The Mount "loft Tel: 01223 263532/262684 Cambridge CB3 7RL Fax: 01223 263948 Organization of Meetings Mr Trevor Waterman 75a Jermyn Street Tel: 0171-930 2954 London SWIY 6NP Fax: 0171-321 0212 Typesetting and Printing Lithoflow Lid 26-36 Wharfdale Road Kings Cross Tel: 0171-833 2344 London NI 9RY Fax: 0171-833 8150 Price: £6 per issue, including back numbers where available. (Please enquire 04 Exec. Officer if sets are required.) The Scientific Instrument Society is Registered Charity No. 326733 © The Scientific lnsVument Society 19')5 Editorial X-ray image of a metal grid taken in THE EM)iF.'.; G.A,ZETTL Crookes' laboratory, but not by him as he -. + .__ was in South Africa when Rontgen's discovery was announced. There is also the metal grid and the X-ray tube used in producing this image. Among the selec- tion of early X-ray tubes are several ~n~anl..,m,u' u '1 tl u+ I* "+~ • ~., ,~ .,.l.~,,~l..,- 6o. all~ III It X |! r-+-''-- ~,~.ll. Jackson focus tubes, the version used in the Middlesex Hospital in c. 18b%7, the tube and induction coil (a fine specimen by Alfred Apps) used by A.A. Campbell Swinton, and a 'Penetrator' tube from MI 4 early 1900 as marketed by W.Watson & Fig.l Eric Fraser's poster fi~r the Post Sons. The ephemera include two X-ray Office celebrating Hertz~ 1888 disco~¢ry. postcards (1914 and 1918) and a charm- ing Christmas card (1902). The core of the Apart from the wrong date, the artist has ....... .. k ~ 0. + ,. :I al + • erroneously turned Hertz's laboratory experi- exhibition is based on the IEE's Silvanus ment into a wireless telegraphy set operated P. Thompson collection, augmented by by a Morse key. An etvcatit~ poster which material from elsewhere such as the teaches us to beu~are of artistic (historical) Science Museum and the British Institute n~constructions. of Radiology. Fig.2 Skeletal lady in The Ladies Gazette Making Waves The University of Siena held a very fine of 7 March 1896. X-ray exhibition in May and in the usual I suggested in March (No. 44), that the Italian manner produced a lavish catalo- theme of the September issue should be report on the AGM). The other papers gue? The most interesting are probably the twin discoveries of wireless and X- were Peter Delehar's 'Wheatstone the early X-ray sets, including a twin- rays, whose centenaries we are celebrat- Abroad?', John Bradley's 'Early Aircraft plate Wimshurst by A. Dall'Eco of Florence which is exhibited with a ing this year. Since no one dissented, this Instruments', my own 'Marconi and the 'Maltese Cross' Crookes' tube and hand- is what I have done.' The scene is set by Transition from Telegraphy to Wireless screen, a fine portable machine with Tony Constable, an historian of early Telegraphy', and Stuart Talbot's 'Astro- Ruhmkorff coil, and an even more wireless and a founding member of the labes and Electrotypes: an Enquiry'. This portable Spanish machine in a suitcase British Vintage Wireless Society. His 'The paper was got ready in time for by SANCHEZ Piedrabuena, 1912. There Birth Pangs of Radio' (Fig. 1) was given publication in this issue. are also a variety of X-ray tubes and at the First Session of the international many other accessories. Another exhibi- conference on 100 Years of Radio, hosted The discovery of X-rays and wireless lion is held in the Montreal Museum of recently by the Institution of Electrical fired the public imagination. The possi- Science and Technology (see 'Current and Engineers in London. ~ Paolo Brenni bilities of the new science-based technol- Future Events'). continues the theme by taking as his ogies seemed to be boundless. subject Eug#ne Ducretet, the foremost Contemporary humorists, cartoonists French maker contemporaneous with (Fig. 2), and poets found them a rich Bologna, the birthplace of Marconi, was Popov and Marconi who pioneered the source of inspiration. 'Lines on an X-ray the venue earlier this year of a beautifully marketing of wireless apparatus. In the Portrait of a Lady' published in Life of designed exhibition (judging by the twenties this firm produced commercial 27 March 1896 has caught the mood catalogue) entitled Radio Fram l~arconi sets that are now prized collectors pieces. splendidly: to the Music of the Unit~erse." ih~ides Ralph Barrett is known for his reenact- unique photegraphs featuring Edouard ment of famous scientific experiments, She is so tall, so slender, and her i~mes Branly, Alexander Popov and Agusto but for the IEE conference he was Those frail phosphates, those carbonates of lime Righi (Marconi's scientific patron), and Marconi. His performance was not only Are well produced by cathode rays of course of Marconi and his family, there credible but also evocative. He demon- sublime, were also exhibited some ve~' interesting strated Marconi's epoch-making experi- By oscillatkms, amperes and by ohms. original pieces of apparatus such as a ment of 1895 (repeated in England on Her dorsal vertebrae are not concealed 'bastardised' 10-inch induction coil used several occasions, including on Salisbury By epidermis, but are well revealed... to allow weak Morse signals coming Plain in 1896). Ralph's models of this from the other side of the Atlantic to be apparatus and that of Popov is the There have also been a number of heard on a telephone receiver, replicas of subject of this issue's 'Facsimile File'. present-day exhibitions, large and small, the Righi tw,cillator (transmitter) and Little of the pioneering wireless appara- several of which have come to my coherer as used by Marconi in his 18•5 tus has survived as most was canniba- attention. The WiJrzburg exhibition was experiments, the famous 'multiple tuner' lised for later experiments. Among the described in the previous Bulletin (p. 3). produced by Marconi Wireless Co. in c+ most perfect surviving specimens are The X-ray exhibition nearest to home 1907, a 'mock-up' (including some those of 1897 in Teyler's Museum which opened in the lEE (London) in August original material) of a Marcimi's ship set will he reproduced in the next issue. and closes on 28 September. ~ This of c. 1902, a fine WWI French-made compact exhibition includes several military transmitter, and a beautiful The celebration of the discovery of X-rays antecedents of the X-ray tube such as an example of the Marconi MR I]4 vah'e is represented by Nell Brown's 'A New intricate early Geissler tube, Crookes' receiver. The story is brought right up to Kind of Rays'. This was one of the five 'Maltese Cross' tube of the 1870s, and a date with the intn~uction of Intemet in papers given at this year's AGM held on (Philip) Leonard tube for the study of the 1970s for military purposes and now 6 July at the Society of Antiquaries in cathode rays which set R6ntgen on the used universally (see Giles Hudson's London (see 'Announcements' for the course of his discovery. There is the first 'Instruments Caught in the Web' below). Bulletin of the Scientific Instrument Society No. 46 (1995) L Exhibition Talks in Museum of the History of Science There will be a series of exhibition talks in association with 'The Measurers' Exhibition. These will be held at 6 p.m. in November. The dates are the 6th (Jim Bennett), 7th (Gerard Turner), 8th (A. Meskens), and the 10th (A. Simpson). Details from the Museum. Antique Telescope Society Fig.3 Set of apparatus for Hertz's u¢~e experiments, including one pair of parah)lic mirrors Hransmitter and receitvr) and a wire frame This American society was founded in polarizer. From Baird and Tatlock Catalogue of 1924, p. 546. 1990 and is dedicated to the study, use and preservation of early astronomical instruments and related material. Their Complex devices such as wireless tele- 5. G. Pancaldi (ed.), D/Marconi alia musica quarterly Journal of the Antique Telescope graphy or X-rays are made up of delle stelle (lh~logna: Gratis Edizioni). The exhibition was held from 9 April - 4 June in Society deals with all aspects of telescope components with different origins which collecting, including technical informa- have been grouped together to create or Bologna and other venues outside Italy are being planned. tion, restoration tips, and historical make use of a new effect. In the history, of papers. They are pursuing the idea of physics new effects were usually created holding a meeting in the UK in 1996 or with existing apparatus. Once the dis- New Director of History of Astronomy Joins Adler Planetarium 1997. Details can be obtained from the covery has been made, the evolution of Secretary, Walter H. Breyer, at 30 Green the original components into increasingly Valley Road, Wallingford, PA 19086, specialised apparatus could begin.
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