1881.] 071 Elasticity vieioed as possibly a Mode of Motion. 621 



rapidly, and sprung back as if tlio water bad elasticity like tbat of 

 jelly, wbcu it was struck by a stiflf wire puslied down tliroiigb tbe 

 centre of tbe cork by wbicb tbe glass vessel containing tbe water was 

 filled. Lastly, largo smoke rings discbarged from a circular or 

 elliptic aperture in a box were sbown, by aid of tbe electric ligbt, in 

 tbeir progress tbrougb tbe air of tbe tbeatro wben undisturbed. Each 

 ring was circular, and its motion was steady wben tbe aperture from 

 wbicb it proceeded was circular, and wben it was not disturbed by 

 anotber ring. Wben one ring was sent obliquely after anotber tbe 

 collision or approach to collision sent tbe two away in greatly changed 

 directions, and each vibrating seemingly like an indiarubber band. 

 Wben tbe aperture was elliptic each undisturbed ring was seen to be 

 in a state of regular vibration from the beginning, and to continue so 

 throughout its course across the lecture-room. Here, then, in water 

 and air was elasticity as of an elastic solid, developed by mere motion. 

 May not the elasticity of every ultimate atom of matter be thus 

 explained? But this kinetic theory of matter is a dream, and can 

 be nothing else, until it can explain chemical affinity, electricity, 

 magnetism, gravitation, and the inertia of masses (that is, crowds of 

 vortices). 



Le Sage's theory might easily give an explanation of gravity and 

 of its relation to inertia of masses^ on the vortex theory, were it not 

 for the essential aeolotropy of crystals, and the seemingly perfect 

 isotropy of gravity. No finger-post pointing towards a way that can 

 possibly lead to a surmounting of this difficulty, or a turning of its 

 flank, has been discovered, or imagined as discoverable. Belief tbat 

 no other theory of matter is possible is the only ground for antici- 

 pating that there is in store for the world another beautiful book to 

 be called " Elasticity, a Mode of Motion." 



[W.T.] 



