When a part of the body only has been exposed to the action of cold,
and the rest kept heated; if, for instance, a person in a warm room
sits so that a current of air coming through a broken pane, should
fall upon any part of the body, that part will be soon affected with
an inflammation, which is usually called a rheumatic inflammation.
From what has been said, it will be easy to account for this
circumstance. The excitability of the part is accumulated by the
diminution of its heat; but at the same time, the rest of the body
and blood is warm; and this warm blood acting upon a part where the
excitability is accumulated, will cause an inflammation; to which,
the more you apply heat, the worse you make it.--From these
considerations, we may lay it down as a fact, and experience
supports us in so doing, that you may in general go out of warm into
cold air without much danger; but, that you can never return
suddenly from the cold into the warm air with perfect impunity.

Hence, we may lay down the following rule, which, if strictly
observed, would prevent the frequent colds we meet with in winter.
_When the whole body, or any part of it, is chilled, bring it to its
natural feeling and warmth by degrees._

But if, for want of observing this necessary caution, a cold, as it
is called, should have seized a person, let us consider what is
proper to be done.

It will, from the preceding reasoning, appear very improper to make
the room where you sit warmer than usual, to increase the quantity
of bed-clothes, to wrap yourself up in flannel, or particularly to
drink a large quantity of barley-water, gruel, or tea, almost
boiling hot, by way of diluting, as it is called, and forcing a