THERAPEUTIC VALUE OF LOCALIZED FARADIZATION. 159 



is not a simple hypothesis ; the active dilatation of vessels is one of 

 the most unquestionable verities which have been brought to our 

 knowledge. I have proved by direct experiment that there are 

 two orders of vaso-motor nerves, acting in opposite directions ; and 

 that their properties are, in the majority of cases, called into play 

 by reflex influence."^ 



M. CI. Bernard reiterated the same opinion, in 1864, in a more 

 explicit manner. "The vascular system," he said, "is subject to 

 the influence of two nervous systems, more or less distinct : the 

 sympathetic system and the cerebro-spiual. Let us inquire what 

 is the function of each of them ; and what part may legitimately 

 be assigned to each in the facts that we have to study. The 

 former — the great sympathetic — has the function of a moderator of 

 the vessels. When irritated, it produces a more or less considera- 

 ble contraction of them, a contraction which forms a certain degree 

 of impediment to the circulation, and hence diminishes its speed. 

 On the other hand, by exciting the filaments of the cerebro-spinal 

 system, we produce a dilatation of the same vessels. Such is the 

 whole mechanism of the nervous influence. With these two modes 

 of action alone — contraction and dilatation of vessels — the nervous 

 system governs all the chymical phenomena of the organism.'"^ 



But, admitting only what has been demonstrated by experiment, 

 M. CI. Bernard is careful to declare that the generalization of the 

 phenomena of active dilatation of the capillary vessels is at present 

 only a hypothesis. 



C. — Necessitij for the existence of dilatator vascular muscles, as 

 moderators of the constrictor vaso-motors. — I venture to advance a 

 new argument, showing the necessity for a system of nerves to 

 moderate the force of the constrictors. 



I am convinced that all muscular action should have its anta- 

 gonist; and that this rule applies as much to unstriped as to 

 striped fibre. Just, indeed, as wherever I have seen deficiency 

 of antagonism in the muscles of animal life, the attitude and con- 

 formation of the limb or part set in movement by the muscles 

 has been altered, so the preservation of the normal calibre of the 

 vessels necessarily depends upon a certain equilibrium between 

 the tonic force of the constrictors and that of the dilatators. Such 

 appears to me to be the light thrown upon the question by my 

 clinical observations. 



If it be objected that this also is only a hypothesis, I reply that 

 a hypothesis resting upon clinical observation is very near the 



® CI. Bernard, ' Medical Times and 

 Gazette,' vol. ii. 1861, p. 51. 

 " CI. Bernard, Influence du 



nerveux sur les phe'nomenes cldmiques de 

 I'organifime, 25" leyon (Revue des cours 

 scieiitifiques, 28 Juin, 1864.) 



