John Kendrick Bangs,
Pursuit of the House-Boat — Chapter II
“ I had expected him to say at once that he had not lost his watch, but had come to see me about the tiara; and to have him take my words seriously was entirely unexpected and overwhelmingly surprising. However, in view of his rank, I deemed it well to fall in with his humor. 'Oh, as for that,' I replied, 'that is a part of my business. It is the detective's place to know everything; and generally, if he reveals the machinery by means of which he reaches his conclusions, he is a fool, since his method is his secret, and his secret his stock in trade. ”
