and Stevenson ascribes our indestructible spirit of mirth to "the unplumbed childishness of man's imagination."
The illustrations given us by these eminent specialists are as unconvincing as the definitions they vouchsafe, and the rules they lay down for our guidance. Whenever we are told that a situation or a jest offers legitimate food for laughter, we cease to have any disposition to laugh. Just as we are often moved to merriment for no other reason than that the occasion calls for seriousness, so we are correspondingly serious when invited too freely to be amused. An entertainment which promises to be funny is handicapped from the start. It has to plough deep into men's risibilities before it can raise its crop of laughter. I have been told that when Forepaugh first fired a man out of a cannon, the audience laughed convulsively; not because it found anything ludicrous in the per-
