other times affect it. When you have been walking out in the snow,
if you come into your room, you will scarcely be able to see any
thing for some minutes. Look stedfastly at a candle for a minute or
two, and you will with difficulty discern the letters of a book,
which you were before reading distinctly; and if you happen to cast
your eyes upon the sun, you will not see any thing distinctly for
some time afterwards.

Let us next consider the matter of heat: suppose water to be heated
lukewarm, if you put one hand into it, it will feel warm; if you now
put the other hand into water, heated for instance to 120 degrees or
130 degrees, and keep it there some time, we will say, two minutes;
if then you take it out, and put it into the lukewarm water, that
water will feel cold, though still it will seem warm to the other
hand; for, the hand which had been in the heated water, has had its
excitability exhausted by the application of heat. Before you go
into a warm bath, the temperature of the air may seem warm and
agreeable to you, but after you have remained for some time in a
bath that is rather hot, when you come out, you feel the air
uncommonly cool and chilling.

Let us now examine the effects of substances taken into the stomach;
and as the effects of spirituous, and vinous liquors, are a little
more remarkable than food, we shall make our observations upon them.

A person who is unaccustomed to drink these liquors, will be
intoxicated by a quantity that will produce no effect upon one who
has been for some time accustomed to take them; and when a person
has used himself to these stimulants for some time, the ordinary
powers which in common support life, will not have their proper