Up went his hands, and getting a good grip on the parachute shrouds, he pulled down hard on the ropes to windward. The chute immediately bellied in and sideslipped into the wind. He dared not overdo the business, and presently righted the chute by the simple expedient of releasing the shrouds. In a fall of one hundred feet, Bill figured he had sideslipped ten. He had seen men spin their parachutes in order to swing aside from some building or other obstacle. He knew that the trick is done by pulling down on one side, then releasing the pressure with a sort of flipping motion. He attempted it, without success; after a few failures gave it up in favor of the easier sideslips.