ABSTRACT
The automatic activity of the nervous elements, like their histological sensibility, is merely one of the special forms of their peculiar vitality. Diffused, in a similar manner, in its most simple forms, through the most elementary organisms, this automatic activity is perfected, and amplified, in proportion as it is distributed through more abundant and more dense agglomerations of cells, which are at the same time endowed with a more intense vital energy. The histological elements, then, secrete, as it were, at the expense of their substance, peculiar autogenic excitations, and project them to a distance in the form of a continuous or interrupted current, thus acquiring a species of power of radiating to a distance the vital forces they have locally evolved. The operations of automatic activity are, then, generally characterized by a series of processes inverse to those of sensibility.
