Interior of Patent Office, Washington, D.C., U.S.A., Keystone View Company, Singley, B. L. (Benjamin Lloyd), United States. Patent Office, 1894, Washington (D.C.).
Interior of Patent Office, Washington, D.C., U.S.A., Keystone View Company, Singley, B. L. (Benjamin Lloyd), United States. Patent Office, 1894, Washington (D.C.)