David's schooling was such as was afforded by the village and he was early apprenticed as a blacksmith.
He earned his way to Oregon with the immigrant train of 1853 by driving a flock of sheep, arriving at Oregon City with his capital reduced to twenty-five cents. Here he worked as a wood cutter, blacksmith, and surveyor's assistant, becoming in a few years a United States deputy surveyor for Oregon and Washington. He ran the base line of Oregon across the Cascades to the Blue Mountains, and the Columbia Guide Meridian north to the Big Bend of that river. In 1869 he surveyed the Dalles-California military wagon road and in 1872 surveyed and alloted lands to the Indians of the Grande Ronde Reservation.
In the meantime he engaged in numerous business and construction enterprises. He built the first railroad in Oregon – a horse railroad around the Willamette Falls, between Oregon City and Canemah. The road yielded dividends of $48, 000. From 1866 to 1868 he was president and manager of the Oregon City Woolen Manufacturing Company. He was a member of the Willamette Falls Canal and Locks Company, which built, and opened on January 1, 1873, the canal around the Willamette Falls, and he served as president of the Oregon Construction Company, which built most of the lines of the Oregon Railway & Navigation Company, of which he was a vice-president and director. He secured profitable contracts (1872 - 78) to carry mail through the Pacific Northwest.
In 1880 he organized the Portland Savings Bank, of which he became president; he was also president of the Commercial National Bank of Portland and a director in many other financial institutions. During these years he was one of the leaders of the Republican party in his state and for most of the time a public official. He served as state senator (1868 - 72); as governor of Idaho Territory (1875 - 76); as representative in the Oregon legislature (1878-79, 1889 - 90); as mayor of Portland (1879, 1881). In 1890 he was the Republican candidate for governor but was defeated by Sylvester Pennoyer. From November 1892 to April 1893 he was minister to Turkey, succeeding in that position another resident of Oregon, Solomon Hirsch. For ten years he served as regent of the University of Oregon. Unlike most bankers he campaigned for free silver (1895 - 96) and served as chairman of a bimetallic conference held at Salt Lake City in May 1895.
He was married in 1861 to Mary R. Meldrum of Salem, Ore. , by whom he had three children.