Percy and a friend, William Dittrick, repeated the trip on September 25, 1887, through the lower half of the Gorge from the Whirlpool to Lewiston, having a thrilling experience. Dittrick occupied one of the air compartments, while Percy sat in the cockpit. Finally, on September 16, 1888, Percy again risked his life in making a voyage through the waters of the Gorge near Lewiston. In this trip he narrowly escaped death and the boat was lost. Elated by his success, Percy now made a wager with Robert William Flack of Syracuse, "for a race through the Whirlpools in life-boats for five hundred dollars a side." The race was set for August 1, 1888, but on July 4th, Flack was first to show that his craft was seaworthy. The boat was of the clinker pattern, had no air-cushions, and was partly constructed of cork. In the presence of an immense concourse of spectators it went first along gaily, but in three minutes the boat was upset and carried into the Whirlpool bottom upwards. It was a frightful spectacle, witnessed by thousands of people. The boat capsized three times; the last time it tossed high in the air. It stood on end for an instant and then it toppled over on poor Flack, who was strapped to the boat helpless and floated about the pool upside down for about an hour, until captured on the Canadian side. Flack's body was only a mass of bruised flesh. Percy meantime, having witnessed the tragedy from the American side, jumped into a trap, and drove to the Whirlpool on the Canadian side where, throwing off his clothes, he leaped into the river and swam for the boat which was now approaching the shore. But he was too late. His courageous feat could not help Flack, who was found dead, hanging on the straps he had placed there to aid him to save his life. In 1889 Walter G. Campbell tried to make the perilous trip in an open, flat-bottomed boat, which he launched above the Rapids. His only companion was a black dog. Campbell, with a life-preserver about his body, stood up, using his oar as a paddle, and boldly drifted with increasing speed toward the seething pool. The trip took about twenty minutes, but, fortunately, the boat capsized before the worst water was reached, and Campbell just managed to struggle to the shore. The poor black dog paid the penalty of his master's folly.