November 15, 1917] 



NATURE 



207 



fully water-borne the vessel is in stable equili- 

 brium, and the turning- right side uppermost is 

 accomplished by permitting- the air to escape from 

 the interior ; the vessel sinks in the water until 

 a draught is reached for which the equilibrium 

 becomes unstable, and the vessel then turns over 

 without further aid until the deck is uppermost. 

 Fig". 2 shows the vessel with the turning opera- 

 tion about half accomplished, and in Fig-. 3 the 

 vessel is seen floating in its ordinary position. 



The first vessel took about six weeks to arrange 

 the boarding and reinforcement, and two days 

 to cast ; three weeks were allowed for the con- 

 crete to set. It is estimated that the next vessel 

 can be done in half the time, since the same 

 shuttering can be used again. 



W. DU BOIS DUDDELL, C.B,E., F.R.S. 



n^HE death of William Du Bois Duddell on 

 ^ November 4, at forty-five years of age, leaves 

 a gap in the ranks of our men of science 

 which it will be difficult to fill. His was a rare 

 and precious g'ift, for he had, in the highest 

 degree, extraordinary patience and scientific 

 instinct. When a problem was set him, however 

 difficult, however insoluble it might appear to be 

 at first, he was never satisfied until he had 

 obtained a solution. It was an inspiration for 

 anyone to have the privilege of helping him in a 

 piece of scientific work. I shall always remember 

 the development of his oscillograph. We were 

 working together on the study of the alternate 

 current arc and were using a laborious " point 

 by point " method for obtaining the curves of 

 current and potential difference. He had set his, 

 mind on the production of an instrument that 

 would record the curves instantaneously, and at 

 this problem he worked continuously. He made 

 the first instrument in his workshop at home and 

 brought it along- to test ; the damping was unsatis- 

 factory, and we set to work to find a method of 

 damping that was efficient. In the end he made a 

 separate channel, with incredibly thin walls, for 

 each strip, and succeeded. It was remarkable 

 that, although the first instrument was designed 

 by eye, the final form of the oscillog-raph, so far 

 as the vibrator was concerned, did not differ very 

 much in its principal dimensions from the original 

 instrument. Theory enabled the best conditions 

 to be determined, but a full understanding of 

 theory did not lead to a very great improvement. 

 Duddell 's instinct as a designer gave the right 

 dimensions from the start. No one who saw it 

 will forget the demonstration that was given by 

 Duddell before the Institution of Electrical 

 Engineers of his instrument, f>erfect in every 

 detail. There is no doubt that its production 

 marked an epoch in the experimental investigation 

 of alternating current phenomena. If genius is 

 an infinite capacity for taking pains, then Duddell 

 had genius of the very highest kind, for his 

 patience was boundless. His gift as an instrument- 

 NO. 2507, VOL. 100] 



maker was hereditary, for he was connected with 

 the great Du Bois family, famous in that home of 

 watchmaking, Switzerland, for its products. 



Duddell's rise to the front rank of scientific men 

 was meteoric. Soon after his paper on oscillographs 

 (the first edition of which had been given before 

 the British Association in Toronto) he read a 

 classical paper on the resistance of the electric arc 

 before the Royal Society. It was in the course of 

 this work that he discovered the " singing arc," 

 which formed the starting point in the develop- 

 ment of the Poulsen arc, now so largely used in 

 wireless telegraphy, and built the first really high 

 frequency alternator. It was necessary, in order 

 to prove his theory, that a current should be sent 

 through the arc of such a frequency that sensible 

 variations in the temperature of the arc could not 

 be produced by it, so he designed and built an 

 alternator giving 120,000 cycles per second, 

 a frequency which at that time no one had 

 attempted to produce by a mechanical alternator. 



Not only was Duddell's gift as an inventor of 

 the highest order ; he had also rare skill as an 

 experimenter ; his experiments always worked. I 

 can never remember having seen a lecture experi- 

 ment of his that failed, while his power of talking 

 clearly was a gift possessed by few; he reached, I 

 think, almost the highest point in his career as a 

 lecturer in the demonstration on " Pressure 

 Rises " that he gave when he was elected presi- 

 dent of the Institution of Electrical Engineers for 

 the second time. The experiments were nearly all 

 difficult, and liable to go wrong, but they all suc- 

 ceeded, and his model of the oscillating arc was 

 a triumph of demonstration. 



Duddell was made a fellow of the Royal Society 

 in 1907, and his was one of the few cases In which 

 election took place at the first time of asking, for 

 he was elected on the first occasion on which his 

 name appeared on the list of prospective new 

 fellows. In 191 2 he was awarded the Hughes 

 medal. He was president of the Commission 

 Internationale de Telegraphic sans Fil. In 1907 

 he was president of the Rontgen Society, and 

 had been hon. treasurer of the Physical Society 

 since 1910. He was a member of the Advisory 

 Council to the Department of Scientific and 

 Industrial Research and of the Board of Inven- 

 tions, and Research of the Admiralty. Last 

 August the honour of Commander of the Order 

 of the British Empire was conferred upon him. 



As a chairman of committees Duddell was 

 always excellent, being businesslike and to the 

 point ; no time was ever wasted when he was in 

 charge. He was no mean linguist, and those who 

 have seen him conduct an International conference 

 will remember his gifts, and the Infinite tact with 

 which he was always able to reconcile the differ- 

 ing points of view and characteristics of men of 

 different nationalities. It is an unspeakable grief 

 to his friends that he has died so young, though 

 few men have ever achieved so much in so short 

 a time ; but he worked himself to death. He was 

 always in his laboratory or his office ; he scarcely 



