In August 1824, he left York Factory for the Pacific, taking the unorthodox Nelson–Burntwood River route, and ascended the Churchill River and Athabasca Rivers to Jasper House at the east side of Athabasca Pass. He crossed the pass on horseback to Boat Encampment and then down the Columbia River, reaching its mouth at Fort George on 8 November. This 80-day journey was 20 days faster than the previous record. He moved the headquarters of the Columbia District to Fort Vancouver, guessing that the south side of the river might fall to the Americans.