104 



SCIENCE. 



[N. S. Vol. XII. No. 290. 



witli the speed, as computed according to 

 Thomson's theory, is shown in the accom- 

 panying curve. Ordinates represent the 

 apparent increase in mass, while abscissee 

 give the corresponding speeds. The speed 

 of light is put equal to unity. It will be 

 noticed that the ordinates remain nearly 

 constant up to a speed of about eight-tenths 

 that of light, after which the variation is 

 rapid. In quantitative experiments on the 

 kathode rays the speed has never exceeded 

 one-half that of light. Previous experi- 

 ments therefore afford no opportunity of 

 testing the theory. The problem of in- 

 creasing the speed still further is certainly 

 a most promising subject of experimental 

 investigation. 



Since the apparent increase in mass is 

 due to the energy of the field moving with 

 the charge, it would appear that the amount 

 of the increase must depend upon the form 

 of the tube through which the rays pass. 

 So far as I am aware, no experiments have 

 heretofore been made to test this point. It 

 may be that the variation, if it exists, is 

 too small to be detected. 



The suggestion has recently been made 

 that perhaps the whole mass of the cor- 

 puscle is fictitious ; that we really have 

 to do with free electric charges, or electrons, 

 existing apart from matter. This view is 

 even more startling than that which makes 

 the corpuscles smaller than atoms. The 

 novelty of the suggestion is certainly not 

 to be regarded as a serious objection. But 

 direct experimental evidence in favor of 

 this view is as yet lacking. Here, too, it ap- 

 pears to me that a quantitative study of 

 the kathode rays at the greatest attainable 

 velocities offers the most promising means 

 of testing the theory. 



We see that in this subject, as in every 

 branch of natural science, each step in ad- 

 vance suggests still more important prob- 

 lems for further study and aids in their 

 solution. In the kathode rays we have 



gained a new weapon with which to attack 

 the great problems of ether and matter. 

 "What results will be achieved no one can 

 predict. But great as have been the ad- 

 vances during the past decade, we can 

 scarcely doubt that the progress during the 

 decade that is just beginning will be even 



S'^^**®''- Ernest Meeritt. 



COENELL UNIVEKSITY. 



3IATHEMATICS AND ASTRONOMY AT THE 

 A3IEBICAN ASSOCIATION. 



The meeting of Section A was arranged 

 with a view to complete co-operation with 

 the Astronomical and Astrophysical So- 

 ciety in the astronomical part of the pro- 

 gram and with the American Mathematical 

 Society in the mathematical part. The full 

 effect of such co-operation was secured by 

 means of joint sessions, Section A meeting 

 in joint session with the Astronomical So- 

 ciety on Tuesday and on Wednesdaj^ morn- 

 ing, and with the Mathematical Society in 

 joint session or as guests, Wednesday after- 

 noon, Thursday, and Friday. From this 

 arrangement Section A received the benefit 

 of adding to its program the papers of the 

 two afi&liated societies and having the pres- 

 ence of their members in its meetings while 

 in turn, it gave the same aid to them. It 

 is to be hoped that every year in which it 

 is practicable some such arrangement for 

 co-operation may be made. 



Eeports of the meetings of the Astronom- 

 ical and Astrophysical Society and the Amer- 

 ican Mathematical Society will be published 

 separately, hence it would be out of place 

 to here discuss any of the papers presented 

 by them. Among the papers of Section A, 

 that of Henrjr S. Pritchett, who is leaving 

 the Superintendency of the Coast and Geo- 

 detic Survey to become President of the 

 Massachusetts Institute of Technology, is 

 of perhaps the widest general interest ; 

 it is on the ' Functions, Oi'ganization and 

 future Work of the U. S. Coast Survey.' 



