NOVEMBEE 20, 1903.] 



SCIENCE. 



663 



ican Association for the Advancement of 

 Science. Since the Physical Society has been 

 one of the aifiliated societies of the American 

 Association ever since its organization, this 

 action was to be expected. It is hoped that 

 this meeting of the society in the west will 

 afford an opportunity for some organizatio)i 

 there which will bring the same advantages 

 to the physicists of the middle west which 

 the meetings in New York have brought to 

 those in the east. 



The first paper, by Dr. P. G. Nutting, was 

 upon the ' Distribution of Motion in a Con- 

 ducting Gas.' In the experiments described 

 in this paper Dr. Nutting used a thermopile 

 in the form of a thin flat disk. This could 

 be mounted in a vacuum tube in such a way 

 as to present either its flat surface or its edge 

 to the direction of the discharge. At low 

 pressures the temperature indications were 

 quite different in the two cases, since in one 

 case the full bombardment due to moving ions 

 and kathode rays was received on the surface 

 of the pile, while in the other case only the 

 movement across the line of discharge was 

 effective in heating. 



A paper on a special type of radioactivity 

 was next presented by Miss Fanny C. Gates. 

 This paper dealt with a peculiarity in the 

 behavior of sulphate of quinine when heated 

 to about 180° C. and then allowed to cool. 

 During the process of cooling the quinine is 

 found to make the air near it conducting; 

 in fact, at first glance the quinine seems to 

 behave for a while much like a radioactive 

 substance. There are strong reasons for be- 

 lieving that the phenomenon is due to some 

 relatively simple chemical change in the 

 quinine, and the case has been cited as an 

 argument in favor of explaining all cases of 

 radioactivity by recognized types of chemical 

 change. Miss Gates finds, however, that the 

 effect produced by quinine obeys entirely dif- 

 ferent laws from tlie similar effect produced 

 by radioactive substances. Experimenting 

 with different electromotive forces and with 

 different distances between plates, she found 

 it impossible to produce saturation in the cur- 

 rent due to the ionization by quinine. Even 

 with plates only 3 mm. apart at a potential 



difference of 900 volts no indication of sat- 

 uration could be observed. Assuming the 

 ionization to be produced by rays emitted by 

 the quinine it was found that these rays are 

 completely absorbed by a thickness of alumin- 

 ium which would scarcely affect the radia- 

 tion from radium or uranium by a noticeable 

 amount. The conclusion reached by Miss 

 Gates is that the phenomenon is entirely dif- 

 ferent from ordinary radioactivity. She in- 

 clines to the view that the ionization is due 

 to rays of ultra-violet light produced by the 

 chemical change and absorbed in the imme- 

 diate neighborhood of the surface. 



A short paper by Mr. W. J. Hammer dealt 

 with certain points connected with excited 

 radioactivity. Mr. Hammer mentioned cer- 

 tain experiments which led him to believe that 

 excited radioactivity was more permanent 

 than is generally supposed, and that while it 

 dies out rapidly at first, it finally reaches a 

 nearly permanent value. Mr. Hammer ex- 

 hibited numerous radiographs taken by him- 

 self and referred briefly to experiments by 

 which animals had been killed by action of 

 Becquerel rays. He also suggested the internal 

 use of radioactive substances in the treatment 

 of disease, in instances where it is imprac- 

 ticable to reach the seat of trouble from with- 

 out. The active rays might be brought to the 

 diseased parts by the use of solutions of radio- 

 active substances or solutions which have been 

 given excited activity. 



In a paper on Van der Waals' a in alcohol 

 and ether Professor E. H. Hall stated the 

 result of calculations intended to test the 

 validity of certain assumptions connected with 

 the well-known Van der Waals equation. The 

 character of the paper is such as to make it 

 difficult to present the results in a brief ab- 

 stract. 



In the afternoon session W. S. Franklin 

 spoke on the ' Misuse of Physics by Biologists 

 and Engineers.' The object of the paper was 

 to call attention to certain misconceptions of 

 fundamental matters in the subject of thermo- 

 dynamics which are common among engi- 

 neers and biologists who have occasion to make 

 applications of physics in their work. Pro- 



