Harry Clarke Robertson was clerk to U.S. Senator John Hipple Mitchell of Oregon. Collection consists of a scrapbook containing photographs, newspaper clippings, postcards and ephemera regarding a 1902 visit to Hawaii of the Senate Committee on Pacific Islands and Puerto Rico, politics, Washington, D.C. social life, and Theodore Roosevelt.

Typed note, signed, from Theodore Roosevelt when he was governor of New York, to George H. Himes, assistant secretary of the Oregon Historical Society, complimenting Himes and the society on their work.