Almon Harris Thompson (1837-1906) was the chief assistant to John Wesley Powell on the second Colorado River expedition begun in 1871. His wife, Ellen Powell Thompson, was Powell's sister. She collected plant and flower specimens on the expedition.
Biographical/historical: Almon Harris Thompson (1837-1906) was the chief assistant to John Wesley Powell on the second Colorado River expedition begun in 1871. His wife, Ellen Powell Thompson, was Powell's sister. She collected plant and flower specimens on the expedition.
