Few, as I have said, are the humorists who can induce this state. To master and dissolve us, to give us the joy of being worn down and tired out with laughter, is a success to be won by no man save in virtue of a rare staying-power. Laughter becomes extreme only if it be consecutive. There must be no pauses for recovery. Touch-and-go humour, however happy, is not enough. The jester must be able to grapple his theme and hang on to it, twisting it this way and that, and making it yield magically all manner of strange and precious things.