apes, and sometimes even their colours.

Let us next consider what happens with respect to heat, which is a
uniform and active stimulus in promoting life. The extensive
influence of heat upon animal life is evident from its decay and
suspension during winter, in certain animals, and from its revival
upon the approach and action of the vernal sun.

If this stimulus is for some time abstracted from the whole body, or
from any part, the excitability accumulates, or, in other words, if
the body has been for some time exposed to cold, it is more liable to
be affected by heat afterwards applied. Of this also you may be
convinced by an easy experiment. Put one of your hands into cold
water, and then put both into water which is considerably warm: the
hand which has been in the cold water will feel much warmer than the
other. If you handle some snow in one hand while you keep the other
in the bosom, that it may be of the same heat with the body, and then
bring both within the same distance of the fire, the heat will affect
the cold hand infinitely more than the warm one. This is a
circumstance of the utmost importance, and ought always to be
carefully attended to. When a person has been exposed to a severe
degree of cold for some time, he ought to be cautious how he comes
near a fire, for his excitability will be so much accumulated that
the heat will act very violently, often producing a great degree of
inflammation, and even sometimes of mortification. This is a very
common cause of chilblains, and other similar inflammations. When the
hands, or any other parts of the body, have been exposed to a violent
cold, they ought first to be put in cold water, or even rubbed with
snow, and exposed to warmth in the gentlest manner possible.

The same law regulates the action of food, or matters taken into the
stomach: if a person have for some time been deprived of food, or
have taken it in small quantity, whether it be meat or drink, or if
he have taken it of a less stimulating quality, he will find that
when he returns to his ordinary mode of life it will have more effect
upon him than before he lived abstemiously.

Persons who have been shut up in a coal work, from the falling in of
the pit, and have had nothing to eat for two or three days, have been
as much intoxicated by a bason of broth, as a person in common
circumstances with two or three bottles of wine.

This circumstance was particularly evident among the poor sailors