332 



DISCOVERY 



Correspondence 



K ADIO-ACTIVITV AND ATOMIC THEORIES 



To the Editor of Discovery 

 Dear Sir, 



Before I left England nine months ago, I was highly 

 interested in the recent advances in radio-activity and 

 in the experiments revealing the nature of the atom and 

 the construction of the elements. 



Can you tell me how the work is progressing, and the 

 names of any very recent books or periodicals dealing 

 with these matters ? I hate to bother you, but you are 

 the only competent authority I know. 



Yours, etc.. 

 Jasmine, Kern County, Gilbert F. Doble. 



California. 

 September 28, 192 1. 



Books Recommended 

 (i) Radio-activity and Radio-active Substances. By 

 J. Chadwick, Ph.D. (Pitman, 35. bd.) Excellent on the 

 physical side of the subject. 



(2) Atomic Theories. By F. H. Loring. (Methuen 

 & Co., Ltd., I2S. 6d.) 



(3) Radioaktivitdt . By Dr. K. Fajans. An excellent 

 synopsis of the chemical side in German. It is published 

 by Vieweg & Co., of Braunschweig, Germany, and should 

 cost in the United States about 75 cents. 



A. S. R. 



SCIENCE AND INDUSTRY 



To the Editor of Discovery 



Sir, 



The Editorial comments on that part of the speech 

 of the President of the British Association which dealt 

 with the relation of science to war cease at the point 

 where they tend to become most fruitful. The more 

 important question, surely, is the value of science to peace. 

 Perhaps this is assumed. But is it not also a fact, to 

 amend the quotation from Sir Edward Thorpe's speech, 

 that an educated public will refuse to give credit to any 

 body of scientific men who employ their talents in devising 

 means to develop and perpetuate a mode of existence 

 which is abhorrent to the higher instincts of humanity ? 

 The harnessing of solar energy in all its forms by men of 

 science has given to civilised mankind a machine of 

 enormous capability of production — and has at the same 

 time dispossessed millions of the necessities of life. 



The men of science are, of course, no more to blame for 

 producing the horrors of peace than for creating the 

 horrors of war, but it seems a pity that Sir Edward Thorpe 

 did not fully develop his argument, and press for scientific 

 men to employ their talents in devising means to develop 

 and perpetuate a mode of social organisation which is 

 acceptable to the highest instincts of humanity, and 

 wherein science would enrich and not destroy the people. 

 Yours, etc., 

 A. J. Lilliman. 

 32 Queen's Avenue, Hon. Sec. and Treasurer, 



Watford. Walford and District Association, 



October 3, 1921. Xalional Union of Teachers. 



ELECTRONS AND ETHER WAVES 

 To the Editor of Discovery 

 Dear Sir, 



Is not the solution of the problem stated by Sir 

 William Bragg in your September issue to be found in 

 the nature of the medium ? It is hard to conceive an 

 incompressible, frictionless fluid, such as the Ether of 

 Space, but if such exists, the analogy of the falling log of 

 wood and the ship 1,000 miles away must require con- 

 siderable modification. We must imagine that the 

 surface of the sea is perfectly rigid, and that therefore 

 none of the energy transmitted by the falling log can be 

 dissipated in forming ripples or waves. 



The sea being formed of an incompressible fluid, would 

 not the energy be transmitted as an impulse to the loose 

 timber in the vessel and, encountering a plank of the same 

 weight as the original log, shoot it up to the same height, 

 eliminating friction ? 



In other words, can there be actual waves in an in- 

 compressible fluid, or do not the waves form only when 

 the impulse encounters matter ? 



Yours, etc., 

 H. Stansbury, 

 Captain R.X. 

 6, Oakmount Avenue, 



Southampton. 

 October 9, 192 1. 



UNEMPLOYMENT 

 To the Editor of Discovery 

 Dear Sir, 



Regarding Professor Knoop's interesting article on 

 unemployment, there is one method of alienating the dis- 

 tress which is seldom touched upon by writers ; namely, 

 the conversion of some of the employee class (either 

 employed or unemployed) into master men by means 

 of a State loan of capital (money, tools, or materials) 

 in cases where the employee has the necessary- good 

 character and trade ability, but lacks the necessary funds. 

 There are many cases at present where unemployed 

 men are working at home at their trade, but are only 

 partially successful on account of the lack of capital 

 necessary to make proper " master" men of them. 



I suppose a State loan on the security of a man's per- 

 sonal character and skill, and at a low rate of interest, 

 would practically mean a State Bank, and would interfere 

 with the great banking interests of the country, and that, 

 therefore, the idea is " scotched " by politicians. There 

 is no doubt that many practical men of good character 

 would be just as successful as men who often have no 

 technical knowledge of the business they engage in, but 

 who entered into it with capital which many men of the 

 former class lack. 



It does not seem a perfect system, from a scientific 

 point of view, that the possession of capital should have 

 such a great advantage over years of accumulated skill 

 and knowledge. 



I remain, yours, etc., 

 Geo. McL.\ggan. 

 Lewes. 

 November 9, 1921. 



