mortify. But, if the limb be put into cold water, rubbed, and gradually exalted to the usual standard of heat, it may be preserved. Where it is to be observed, that the heat of water, while fluid, is above the freezing point, and, consequently, greater than that of a frozen limb.
It may somewhat confirm this reasoning, to give a similar explication of some of the phænomena of glass bubbles, made by dropping melted glass into water. We may suppose then, that these fall at once into powder, when broken at their points, because the cold water has so far reduced the sphere of attraction, that all the parts of the bubbles are agitated beyond this, by breaking their points. But if a bubble be heated, and its parts brought to a larger sphere of attraction by the agitations from heat, it will no longer fall to powder when broken at its point. It may also have its parts ground away at pleasure, without falling to powder, because grinding agitates all the contiguous parts with strong vibrations, like heat, and enlarges the sphere of their attractions.
Eighthly, When the parts contiguous to a mortified slough have a sufficient heat in them, excited by the vis vitæ, or warm applications, the vibrations attending this life and heat of the parts ought to help to shake off and separate the mortified slough, i.e. to stop the mortification; which is agreeable to the fact. Hence mortifications from external cold, in bodies otherwise healthy, will come to separate soonest, and most perfectly, as it is frequently seen in cold climates. Hence also mortifications happening in the acute distempers of young persons, if they stop at all, stop sooner than those in the extreme parts of old persons.
Ninthly, It is said that cold water, sprinkled upon the distended limbs of malefactors upon the rack, renews and augments their pains. Now, we may here suppose, that the parts had, in some measure, begun to accommodate themselves to their distended state, by getting new and enlarged spheres of action; when therefore the cold water endeavours to contract the parts again, and to narrow the spheres of action, the limbs still continuing distended by the rack, it is evident, that a strong conflict, with violent vibrations, and the solution of continuity, must ensue. Was the limb released first, and then cold water applied, it might contribute, as in sprains, to restore the parts to their former state, without exciting any such violent conflict. The good effects of vinegar, verjuice, spirit of wine, and other contracting liquids, in sprains, are to be explained upon the same principles.
Tenthly, Hot or cold water feels hotter or colder, respectively, when the hand is moved in it, than when it is kept at rest. For the hand, when at rest, has time, a little to check or exalt the vibrations in the contiguous hot or cold water.
Eleventhly, When a person goes into cold water leisurely, he
