I have several times been saved by this mysterious interposition, when I was manifestly in extreme peril. It has been common, all my life, for smart people to perceive in me an easy prey for selfish designs, and I have walked without suspicion into the trap set for me, yet have often come out unscathed, against all the likelihoods. More than forty years ago, in San Francisco, the office staff adjourned, upon conclusion of its work at two o'clock in the morning, to a great bowling establishment where there were twelve alleys. I was invited, rather perfunctorily, and as a matter of etiquette--by which I mean that I was invited politely, but not urgently. But when I diffidently declined, with thanks, and explained that I knew nothing about the game, those lively young fellows became at once eager and anxious and urgent to have my society. This flattered me, for I perceived no trap, and I innocently and gratefully accepted their invitation. I was given an alley all to myself. The boys explained the game to me, and they also explained to me that there would be an hour's play, and that the player who scored the fewest ten-strikes in the hour would have to provide oysters and beer for the combination. This disturbed me very seriously, since it promised me bankruptcy, and I was sorry that this detail had been overlooked in the beginning. But my pride would not allow me to back out now, so I stayed in, and did what I could to look satisfied and glad I had come. It is not likely that I looked as contented as I wanted to, but the others looked glad enough to make up for it, for they were quite unable to hide their evil joy. They showed me how to stand, and how to stoop, and how to aim the ball, and how to let fly; and then the game began. The results were astonishing. In my ignorance I delivered the balls in apparently every way except the right one; but no matter--during half an hour I never started a ball down the alley that didn't score a ten-strike, every time, at the other end. The others lost their grip early, and their joy along with it. Now and then one of them got a ten-strike, but the occurrence was so rare that it made no show alongside of my giant score. The boys surrendered at the end of the half-hour, and put on their coats and gathered around me and in courteous, but sufficiently definite, language expressed their opinion of an experience-worn and seasoned expert who would stoop to lying and deception in order to rob kind and well-meaning friends who had put their trust in him under the delusion that he was an honest and honorable person. I was not able to convince them that I had not lied, for now my character was gone, and they refused to attach any value to anything I said. The proprietor of the place stood by for a while saying nothing, then he came to my defence. He said: "It looks like a mystery, gentlemen, but it isn't a mystery after it's explained. That is a _grooved_ alley; you've only to start a ball down it any way you please