Note 26 — DISSERTATION II. CONTINUED.

When two parts are affected at the same time, in consequence of an agent operating quickly on one of them, they commonly exhibit the sympathy of association, which takes place suddenly, but generally at first lasts only for a short time, if the parts be distant; but, if the original disease still continue, it may spread, inch by inch, until it arrives at the part which was formerly affected, and which is again affected more permanently, by the same kind of sympathy taking place, but in a different way. In the first case, we have the sympathia consociationis interrupta; in the second, the sympathia consociationis serpens. It is this last which is the cause of the extension of all action in a part, and which, when strongly excited, overcomes the natural tendency to the exhibition of the sympathy of equilibrium. It is, however, more difficult for local action to spread by degrees to parts which evince the sympathy of equilibrium than other parts; and these, in general, are longer of being affected. Thus, when inflammation begins in the skin, it can much more easily spread along the skin than dip down to the muscles.