vasion of microbes. We know that the leucocytes have the property of moving and putting out prolongations, by means of which they surround foreign bodies and force them into the mass of their protoplasm. They behave in a similar way toward microbes, which, once surrounded, are destroyed by a real intracellular digestion, and we give the name of phagocytism to the whole of these operations. Now, dilatation of the peripheric vessels occurs in sthenic emotions, in which it is manifested by ruddiness, increase of volume, and functional exaltation. In asthenic emotions, on the contrary, inverse phenomena betray a diminution of circulation and a decrease in the caliber of the vessels, and consequently a condition unfavorable to the sally of the white globules and to phagoyctism. Asthenic emotions, from this point of view, lead to the same conditions as traumatisms, fatigue (Charrin and Bogen), chill (Pasteur, Wagner, Platania, Charrin), inanition (Canalis and Morpurgo), loss of blood (Serafini), and nervous sections (Charrin and Ruffer, Roger and Herman).
Not only do the conditions of the vessels change, but the phagocytes and the white globules especially are modified as to their vitality and their chimiotaxy, and their property of being attracted or repelled by the microbes or their products of secretion vary under the same circumstances. Under the influence of cold the white globules tend to become paralyzed. MM. Massert and Bordet, whose experiments seem to demonstrate the absence of a relation between the chimiotaxic action of the leucocytes and the condition of the vessels, admit that under defective conditions of nutrition the whole organism is more easily impregnated by a poison which provokes at every point the chimiotactic activity of the leucocytes, which then have no occasion to direct themselves toward any particular point. The modifications in the composition of the blood after nervous excitements and under emotions which we have mentioned can also be adapted to this theory. Experimental data show that in all conditions in which nutrition is deficient—and painful emotion is one of these conditions—infection is caught more easily. Evidence of this is not only derived from animals; I have had occasion to observe on man several facts which give support to results obtained in the laboratory.
Having to revaccinate patients in my practice, I inoculated a dozen hemiplegic persons symmetrically in both arms in order to see whether the paralyzed side would offer a different resistance to the virus. Real vaccine was not developed in any of these patients, all of them having been vaccinated not more than three or four years before. Upon three of them only were developed pustules of false vaccine, exclusively on the hemiplegic side of one, and with a marked predominence of volume and duration on the other two.