334 



NATURAL SCIENCE 



[November 



purpose of a kind of neuroplasma and receive whatever shape you 

 intend to impress ou it, viz., that of a multipolar cell (fig. 17), a 

 cylindrical conductor (fig. 5), etc. Its vibrations may be obtained 

 by the action of azotic or chromic acid, or by means of a small rod 

 or an ant's leg. The vibrations can be verified by fixing a small 

 paper lever on the surface of the liquid, or by receiving a luminous 

 ray reflected on a screen. 



Some incidents of nervous transmission are rendered evident by 

 a differential manometer of caoutchouc full of water. 



-JaU^ 



Diagrams illustrating Experiments on Ai-tificial Nerves. For explanation see the text. 



(a) Nervous vibration in general. — 1. The rubbing of a nerve 

 of mercury with a soft feather is enough to make it vibrate. 



It is, therefore, probable that a very slight mechanical or 

 chemical action (e.g. light) would be able to shake the band axis that 

 is, in general, carefully isolated in the middle of a mixture of fats 

 and albuminous matters. The impressionability of liquids is ex- 

 ceedingly delicate. Milne-Edwards * has in the experiments per- 



1 Physiologie et Anatomie Comparee, Vol. xii., p. 523 ; Jamin, Cours de physique 

 <le 1'Ecole Polytechnhjue. Paris, 1803. 



