Templeton, meanwhile, had been anxiously weighing the claims of the other ideas that jostled in his brain.  He wanted to perfect his automatic hair-cutter; to experiment with what he called, in advance, a "levitator"—a contrivance for enabling an aeroplane to rise more rapidly; to test his notion of a tar entanglement, and various other sound schemes.  Unfortunately the incomplete hair-cutter had been confiscated by his head master, and it would take weeks to construct a new one.  The levitator was out of the question at present, for it would cost a good deal more than the two pounds odd which remained out of his aunt’s gift.  Several ideas were unworkable for the same reason, and he had almost resolved on the tar entanglement when, with that suddenness to which inventors are accustomed, a quite new idea shot into his mind.