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SCIENCE 



Feidat, December 10, 1915 

 contents 



The Aerial Transmission Problems: Pbofessoe 

 M. I. PUPIN 809 



The Calorimeter as the Interpreter of the Life 

 Processes: Professor Graham Lusk .... 816 



Obstacles to Sesearch: Professor C. M. Jack- 

 son 819 



J)r. Charles Frederioh Holder: Dr. George F. 

 KuNZ 823 



Scientifio Notes and News 825 



and Educational News 829 



Discussion and Correspondence: — 

 A Semarlcable Eclipse: Dr. John N. Stock- 

 well. The Degree of Exactness of the 

 Gamma Function necessary in Curve Fit- 

 ting: Dr. Raymond Pearl. The Origin of 

 Lost Biver and its Giant Potholes: J. W. 



GOLDTHWAIT 830 



Scientific Boohs: — 



Goddard on Feeble-mindedness: Dr. C. B. 

 Davenport. Korschelt 's Handworterbuch 

 der Naturwissenschaften: Db. Eot L. 

 Moodie 837 



Proceedings of the National Academy of 

 Sciences: Professor Edwin Bidwell Wil- 

 son 840 



Special Articles: — 



Interferences with Two Gratings: Carl 

 Baeus. Effect of X-Eay on the Resistance 

 to Cancer in Mice: James B. Murphy, John 

 J. Norton 841 



Societies and Academies: — 



The Biological Society of Washington: M. 

 W. Lyons, Jr. The American Mathematical 

 Society: Professor F. N. Cole 843 



THE AERIAL TRANSMISSION PROBLEMS-^ 

 The title of my address suggests that I 

 propose to discuss the problems connected 

 with wireless telegraphy and telephony. It 

 should be observed, however, that ordinary 

 telegraphy and telephony and electrical 

 transmission of large amounts of power is 

 aerial transmission and faces some of the 

 problems which confront us to-day in 

 wireless transmission. But, of course, the 

 problems of aerial transmission in their 

 relation to wireless telegraphy and tele- 

 phony present their most interesting aspect 

 and I shall, therefore, devote most of my 

 time this evening to this particular aspect, 

 of the problem of aerial transmission. 



Permit me now to differentiate, briefly, 

 wireless transmission from ordinary elec- 

 trical transmission. 



MSS. intended for publication and boots, etc., intended for 

 review should be sent to Professor J. McKeen Cattell, Garrison- 

 On-Hudson. N. Y. 



EA RTH 



Fig. 1 represents the simplest form of 

 ordinary electrical transmission. A wire, 

 ACB, is connected to the earth at each end. 

 A generator station at A sends electrical 

 energy to receiving apparatus stationed at 

 B. The motion of electricity started at A 

 is transmitted along the wire C to the sta- 

 tion B and then is completed through the 

 conducting ground between B and A. 



1 An address delivered before the National Acad- 

 emy of Science, at its meeting ia New York, No- 

 vember 15, 1915. 



