46 A, E. HILTON ON THE NATURE OF LIVING ORGANISMS. 



Such materials, absorbed in a state of solution, serve partly as 

 nutriment, for the repair or increase of the plasm itself ; and 

 partly for the building up of the structure of the organism. 

 Between the tissues and liquids of plants and animals, numberless 

 catalytic processes are constantly going on, producing an endless 

 variety of results ; and when the chemical processes are reversible, 

 the catalytic stimulus operates in either direction. In this way, 

 also, the vital balance is preserved, which is so essential to the 

 welfare of the organism. 



This brings us back to the electric phase of our subject ; because 

 catalysis, like chemical affinity, can only be explained by move- 

 ments of electrons. It is not true that " electricity is life," 

 because all matter, living or dead, is electric ; but all life has 

 electricity for one of its essential elements, and the strength of 

 the vitality of an organism may be gauged by measuring the 

 intensity of the electrical disturbances involved in its changes. 

 On the other hand, when animation is suspended by means of 

 chloroform, the electrical signs of life are also suppressed. All 

 nervous impulses are likewise known to be accompanied by 

 electrical alterations ; and here, again, the organism is automatic, 

 because the persistent tendency of its electricity is to re-establish 

 the equipoise between the higher and lower potentials, which is 

 constantly disturbed by occurrences within and without. 



The suitability of plasm for utilising, and yet conserving, its 

 electric power is very notable. Complicated carbon compounds 

 are among the best insulators ; and as molecules of plasm are 

 comparatively large and loose, multitudes of electrons are effec- 

 tively imprisoned within them. Pure water, again, is an almost 

 perfect insulator ; and water enters largely into the constitution 

 of plasm. Water, moreover, has a remarkable power of splitting 

 up molecules of other bodies into smaller particles, and these 

 particles, diffused through the water, act as " ions " — that is, 

 carriers of electrons. The water in plasm, therefore, is not only 

 a medium for the circulation of food materials and refuse, but, 

 being thus " ionised," it also distributes the electrical energy, 

 while at the same time conserving it. As the speed of " ions " is 

 somewhat retarded in water, the electric energy, although working 



