550 



NATURE 



[January 13, 19 16 



and to Henri Bocquillon, for his botanical and thera- 

 peutical studies of tropical plants; 2500 francs from 

 the interest ori the Breant prize to M. Brumpt, for his 

 Avork on parasitology ; the Godard prize to Noel Hall^, 

 for his researches on chronic renal tuberculosis ; a 

 mention to Henri Vignes, for his notes and researches 

 on menstruation ; the Baron Larrey prize is not 

 awarded ; the Bellion prize to Henri Gougerot, for his 

 memoir on the treatment of syphilis in practice ; a 

 very honourable mention to Emile and Camille Guillot, 

 for their work entitled "The Healthy House"; the 

 Mfege and Argut prizes are not awarded; the Chaussier 

 prize is not awarded, but an encouragement (500 

 francs) is given to Raoul Benon, for his book on post- 

 traumatic psychic and nervous troubles ; the Dusgate 

 prize is not awarded, but* Arcangelo Creazzo receives 

 a mention for his work on real and apparent death. 



Physiology. — The Montyon prize to Andr^ Thomas, 

 for his work on the brain ; the Philipeaux prize to 

 Henri Stassano, for the whole of his work in physio- 

 logy ; the Lallemand prize between Jules Glover (1000 

 francs), for his work on the physiology of the voice 

 applied to art and industry, and Pierre Achalme (800 

 francs), for his book on electrotonics and biology ; no 

 memoirs have been received dealing with the subject 

 proposed for the Pourat prize, and the prize is postponed 

 to 1917; the Fanny Emden prize to Jean Chatanay, 



Statistics. — The Montyon prize (1000 francs) to 

 Fernand de Montessus de Ballore, for his seismological 

 work. 



History of Sciences. — ^The Binoux prize between 

 Albert Anthiaume, for his work on the history of 

 nautical science, F. Marguet, and George Sarton. 



General Pme5.— Berthelot medals to Gabriel Ber- 

 trand, M. Vigu^er, and Paul Pascal ; the Becquerel 

 prize between M. Arnaud (2000 francs), Jean Merlin 

 (ytjo francs), and M. Rabioulle (750 francs) ; the Gegner 

 prize (3800 francs) to G. Cesaro, for his work in 

 descriptive crvstallography ; the Lannelongue fund, the 

 interest is divided between Mme. Cusco and Mme. 

 Riick ; the Gustave Roux prize to Lucien Berlnnd, the 

 prize reserved from iqi4 to Georges Lery; the Tremont 

 prize to Charles Fremont; the Wilde prize to Com- 

 mandant Batailler, for his work in experimental 

 mechanics relating to ballistics; the Lonchampt prize 

 to Fernand Jadin and Albert Astruc, for their work on 

 the presence and estimation of arsenic and manganese 

 In the vegetable kingdom ; the Saintour prize to A. 

 Blondel. for his work on the theory of tides; the 

 Henri de Parville prize between Jean Escard (1000 

 francs), for his books dealing with scientific and tech- 

 nical Questions, Gustave Loisel (1000 francs), and 

 Albert Buisson (500 francs) ; no memoir dealing wnth 

 the subject proposed for the Vaillant prize was re- 

 ceived, and the prize is postponed to iqiq: the Grand 

 prize of the Physical Sciences to Henry Hubert, for 

 his ':tudv of the p-eolorfy of French Western Africa ; the 

 Le Conte prize to Sir Almroth Wright, for his researches 

 in antityphoid vaccination; the Petit d'Ormov and 

 Laplace and Rivot prizes are not awarded. 



WIRELESS COMMUNICATION. 

 COME notes on the present state of wireless tele- 

 ^ graphy were communicated by Dr. M. I. Pupin 

 in the course of a lecture which he delivered before 

 the National Academy of Science in New York, on 

 "Aerial Transmission Problems." None of the points 

 raised by Dr. Pupin were entirelv new, as they have 

 been frequently discussed in both continents without 

 being appreciably helped towards solution. But the 

 manner in which they were presented and illustrated 

 assisted towards a better understanding of the formid- 

 able character of the obstacles in the way of extending 

 the distance of wireless communication. These 

 NO. 241 1, VOL. q61 



obstacles are due mainly to the interference produced 

 by electrical waves, which are passing through the 

 terrestrial atmosphere continuously, and it is not until 

 we attempt to magnify the minute signals coming 

 from a distant transmitting station that we are really 

 aware of their presence. An engineer who took part 

 in the recent long-distance wireless telephony trials 

 and listened for the famous telephone message 

 from Arlington, reports that at times " it was drowned 

 completely in a roar of musketry," due, of cours'e, to 

 the action of the electrical waves produced by the 

 incessant electrical discharges in the atmosphere. All 

 attempts up to the present which the "practical" 

 wireless engineer has made in the direction of over- 

 coming these disturbances have consisted in increas- 

 ing the power applied at the tran.smitting station so 

 as to make the incoming signals at the receiving 

 station stronger than the signals made by the "static." 

 Ordinary electrical tuning is not suflficient for the pur- 

 pose, because every system which is highly selective 

 through ordinary tuning' is also highly sonorous ; 

 every tap of the static will cause it to vibrate, and 

 it will vibrate in the same way as when it is under 

 the action of the signalling waves. The method advo- 

 cated by Dr. Pupin involves the use of a sectional 

 wave conductor between the antenna and the receiv- 

 ing apparatus, which will not transmit electrical waves 

 of a frequency higher than a given range of fre- 

 quencies. By this means, he states, " the station 

 becomes an ear, which Is quite sensitive for frequencies 

 which are in the vicinity of the signalling frequency, 

 which is deaf to frequencies which are considerably 

 beyond this range, as most static disturbances are." 

 "Similarly," he adds, "a sectional wave conductor can 

 be constructed which is quite responsive to frequencies 

 in the vicinity of the signalling frequency, but absorb 

 almost completely everything Ijelow this range." 



Dr. Pupin corrects the popular misconception that 

 wireless telegraphy formed its first roots in German 

 soil, whereas in reality it is a particular case of the 

 oscillatory motion of electricity discovered bv Joseph 

 Henry, and the laws of which were formulated bv 

 Kelvin. It is true that Hertz employed these oscilla- 

 tjons more skilfully than anybody else did prior to his 

 time, and thereby succeeded in improving experiment- 

 ally the complete validity of the physical foundation 

 of the electromagfnetic theory which was conceived 

 and formulated by Clerk Maxwell, and paved the 

 way for Mr. Marconi. Dr. Pupin claims that "Mar- 

 coni discovered wireless telegraphy," but he altogether 

 ignores the achievements of Branly, of Lodge, of 

 Popoff, and others. It cannot be said of Mr. Marconi 

 that he discovered the principles or invented the 

 primary appliances upon which the transmission of 

 electromagnetic waves are based. He accomplished 

 his result by combining, in the utilisation of known 

 principles, features which had been disclosed by others, 

 which he improved and co-ordinated, with additional 

 features of his own invention. 



Mr. E. H. Colpitts, the research engineer of the 

 Western Electric Company of America, under whose 

 direction the apparatus was developed and the experi- 

 ments conducted which resulted a few weeks ago in 

 the wireless transmission of speech between Arlington, 

 U.S. .A., and Honolulu, on one hand, and Arlington 

 and Paris on the other, discusses in the Scientific 

 American the significance of the recent achievement in 

 long-distance wireless telephony. The technical details 

 of the system have alreadv been described, so far as 

 they are available, and chief interest in Mr. Colpitts's 

 article lies in his views regarding the future of wire- 

 less telephony. He does not consider that it will dis- 

 place line telephonv, and even if it is physically possible 

 and can be usefully employed, it must fail to be com- 

 mercially practicable. Atmospheric disturbances were 

 found to be a great drawback, while another dil!icultv 



