"How does it create a vacuum?"
"By the contraction of a muscular pimple in the centre," said Tom, in a moment of inspiration.
"And what makes this pimple contract?"
Tom lost his head, and was about to say "electricity," when he happily checked himself and substituted "muscular action."
"Very good," said the examiners, and the student breathed again. The taller one returned to the charge, however, with, "And this muscle—is it composed of striped fibres or non-striped?"
"Non-striped," shrieked Tom at a venture, and both examiners rubbed their hands and murmured, "Very good, indeed!" at which Tom's hair began to lie a little flatter, and he ceased to feel as if he were in a Turkish bath.
"How many teeth has a rabbit?" the tall man asked suddenly.
"I don't know," the student answered with candour.
The two looked triumphantly at one another.
"He doesn't know!" cried the goggle-eyed one decisively.