81 
his experiments are composed of a substance highly active 
under the microscope, and the fact that osmose is most 
shown by very dilute solutions (1 p.c. or less) is entirely in 
accordance with the electric origin of the phenomenon. 
I consider it to be established experimentally that the 
microscopic movement is due to electric action, and if I may 
venture to suggest a somewhat speculative explanation of 
the action I would point to the experiments of M. Wiede- 
mann on electric osmose. It was first observed by Mr. 
Porret that when the poles of a battery are placed in two 
portions of water separated by a porous division, not only is 
some of the water decomposed, but another and far larger 
portion is impelled towards the negative pole. M. Wiedemann 
having exactly investigated the phenomenon found that for 
one part of water decomposed 5,000 parts were transported 
through the porous septum. This impulsion is greater as 
the resistance of the liquid is greater, and ceases altogether 
when sufficient acid or salt is added to render it a good 
conductor. Every particle which is thrown into a polar 
condition by the action of water must be capable in a 
minute degree of exerting a similar force. In ordinary 
osmose the particles being fixed cause a transportation of 
the fluid ; in microscopic movement, on the other hand, the 
particle is free to move, and the reaction of the liquid 
probably produces those movements which are visible in 
the microscope. 
Although I have chiefly confined my attention to in- 
organic substances, I have also found that all organic solid 
particles which are sufficiently small exhibit the movements 
in a high degree. Albumen, dextrin, grape or cane sugar, 
