From 1890 to 1893 he worked for the U.S. Coast and Geodetic Survey and developed triangulation methods of surveying which were less expensive and more accurate than those employed up to that time.
Mula sa 1890 na 1893 ay nagtrabaho siya para sa US Coast at Geodetic Survey at binuo triangulation pamamaraan ng pagtilingin na kung saan ay mas mura at mas tumpak na kaysa sa mga trabaho hanggang sa oras na iyon.