Canadian explorer David Thompson noted a point of sand in his diary in 1809 that he believed was near the site of present-day Sandpoint. Settlement began there in the 1880s, and the panhandle's timber wealth drew railroads that greatly increased the number of settlers. Across Sand Creek stood the Humbird Lumber Company, one of the largest sawmills in the area, incorporated in 1900 by Frederick Weyerhaeuser and John A. Humbird. Humbird held more than 150,000 acres of forest and operated a highly mechanized mill powered by large steam boilers, but by 1931 the depletion of white pine forced the mill to close, sending hundreds of men into the Great Depression, and a fire in July 1940 burned the empty sawmill and ended a major chapter in Sandpoint's timber history. As northern Idaho's forests were being harvested, Sandpoint also developed a metals industry when the Panhandle Smelting & Refining Company began operations in June 1907 to smelt ores shipped from Trail, British Columbia. Within its first days the smelter produced its first run of lead bars, using a tandem 150-horsepower Corliss steam engine and electrical machinery, and workers on three shifts set a record with the largest run in a 24-hour period when the smelter produced 168 lead bars weighing 115 pounds in July 1907. Although the company expanded capacity to 600 tons per day by adding furnaces, a suit filed in 1909 against the company's president for dishonesty began its decline, and a court-ordered sheriff's sale in 1913 ended Sandpoint's smelting history.