19. We have taken as an illustration heat generated by the movement of a wheel, because it is a common effect known to all and easier to comprehend; but it had been more exact to say, that in the combination of elements needed to form organic bodies, they are developed by electricity. Organic bodies are therefore veritable electric batteries which operate to the extent that the elements composing them are in a condition to generate electricity, which is life. When these conditions are arrested, death ensues. The vital principle can be none other than a particular kind of electricity designated under the name of animal electricity, evolved during life by the action of the organs, of which the production is arrested by death owing to the cessation of this action.