light
degree of what medical men call opisthotonos. Thus, then, without
contending that the phenomena of laughter in all their details are to be
so accounted for, we see that in their _ensemble_ they conform to these
general principles:--that feeling excites to muscular action; that when
the muscular action is unguided by a purpose, the muscles first affected
are those which feeling most habitually stimulates; and that as the
feeling to be expended increases in quantity, it excites an increasing
number of muscles, in a succession determined by the relative frequency
with which they respond to the regulated dictates of feeling.

There still, however, remains the question with which we set out. The
explanation here given applies only to the laughter produced by acute
pleasure or pain: it does not apply to the laughter that follows certain
perceptions of incongruity. It is an insufficient explanation that, in
these cases, laughter is a result of the pleasure we take in escaping
from the restraint of grave feelings. That this is a part-cause is true.
Doubtless very often, as Mr. Bain says, "it is the coerced form of
seriousness and solemnity without the reality that gives us that stiff
position from which a contact with triviality or vulgarity relieves us,
to our uproarious delight." And in so far as mirth is caused by the gush
of agreeable feeling that follows the cessation of mental strain, it
further illustrates the general principle above set forth. But no
explanation is thus afforded of the mirth which ensues when the short
silence between the _andante_ and _allegro_ in one of Beethoven's
symphonies, is broken by a loud sneeze. In this, and hosts of like
cases, the mental tension is not coerced but spontaneous--not
disagreeable but agreeable; and the coming impressions to which the
attention is directed, promise a gratification that few, if any, desire
to escape. Hence, when the unlucky sneeze occurs, it cannot be that the
laughter of the audience is due simply to the release from an irksome
attitude of mind: some other cause must be sought.

This cause we shall arrive at by carrying our analysis a step further.
We have but to consider the quantity of feeling that exists under such
circumstances, and then to ask what are the conditions that determine
the direction of its discharge, to at once reach a solution. Take a
case. You are sitting in a theatre, absorbed in the progress of an
interesting drama. Some climax has