688 



EEPORT 1893. 



FRIDAY, SEPTEMBER 15. 

 The following Papers were read : — 



1. Beport on the Present State of our Knowledge of Electrolysis and Electro- 

 chemistry. By W. N. Shaw, F.B.S., and the Rev. T. C. Fitz- 

 PATRICK. — See Reports, p. 146. 



2. On the Connection between Ether and Matter. 

 By Dr. Oliver J. Lodge, F.B.S. 



The author reported progress in his experiments to examine into the connection 

 between ether and matter, and concludes that at least unless matter is electrified 

 there is no stress-connection between these two bodies of a kind to interfere with 

 their relative motion. 



From this he draws several conclusions, one of which is that radiation is due to 

 the motion of electrified parts of molecules — not to the molecule as a whole. 



3. Ow a Mechanical Analogue of Anomalous Dispersion, 

 By R. T. Glazebrook, M.A., F.B.S. 



In the figure A, B, C represent a series of particles, each of mass w, connected 

 together by strings of length a. The particles can vibrate on the plane of the 

 paper, and a wave of simple harmonic vibration will travel along them with 

 definite velocity. The tension in the string is F. Each particle is connected as 



shown by two springs to two masses A,, A^ ; Bj, B^,, &c., respectively, the masses 

 of these particles being M. This second series of particles is connected by springs 

 to the sides of the frame. The period of vibration of one of the particles, such 

 as A, when the string joining it to the particles on either side is cut and the 

 masses Aj, Aj are held fixed, is t^ ; the period of vibration of a particle such as 

 Aj under the action of the spring joining it to the frame alone is Tg. The string 

 joining the particles A, B, C is continued, and carries a series of particles each of 

 mass wjo unconnected to any springs. Suppose a wave of period T to be travelling 

 with velocity Vg along this string; on reaching the particle A the velocity 

 becomes V, and it can be shown that 





m 



win 



, r, T^ m T* T„« "1 



Suppose now that f^ is large, and let T be less than t^ but greater than T^, ; 

 suppose also that m is greater than 7)i^. Then fj.- is greater than unity ; a wave 

 travels along A, B, C, but with less velocity than along the external row of 



