Frustrated but undaunted, Mackenzie vowed to reach the Pacific. After spending a year in England studying astronomy, navigation, and geography, he led another expedition into the Canadian wilderness in May 1793.
The ten-man party and its equipment were loaded into a single 25-foot birchbark canoe. The canoe, sturdy but light, carried the group as it swiftly paddled west up the Peace River.
After two weeks, Mackenzie spotted the peaks of the Rocky Mountains in the distance. The river narrowed and entered chasms, accelerating the current and crashing the water into white foam over treacherous rocks.
Abandoning their paddles, the men struggled to pole and pull the canoe upriver. The water often caught the canoe and smashed it against rocks, tearing holes in its hull. The men stopped frequently for repairs, and some wondered whether the journey was doomed to failure. But Mackenzie refused to give up.
He ordered the men to carry the canoe and its supplies overland, an agonizing journey through forests and fields thick with underbrush. After three days the exhausted party had traveled past the rapids and was able to navigate the Peace River again.
For another three weeks, the group struggled west, finally meeting an Indian who guided them to a river that flowed toward the Pacific. But the trip downstream was often more difficult than paddling upstream.
At one point the men lost control of the canoe, running into rocks that tore off the bow and stem and spilled the supplies into the swirling current. The men thought certainly that they would turn back. But Mackenzie ordered them to repair the canoe, and they continued. On July 20, 1793, the party finally spilled out of a river into a salty bay just north of Vancouver Island.
After ten weeks of grueling travel, Mackenzie had reached the Pacific. He took navigational readings and guided the party home. In 1801, he published an account of his travels in Voyages from Montreal.
One of the most enthusiastic readers of the book was an American president named Thomas Jefferson.