The E. Clarke and Julia Arnold House, on the west edge of Columbus, Wisconsin, is a Frank Lloyd Wright-designed Usonian home built in 1955 and 1956 for attorney E. Clarke Arnold, Julia Arnold, and their family. Using Wisconsin limestone, redwood board-and-batten, and glass, it reflects Wright’s late diamond module designs, based on 60- and 120-degree angles. Originally planned as a V-shaped house with living and bedroom wings around a central core, it was expanded after twins were born. Wright approved the addition in 1959 before his death, and John H. “Jack” Howe revised it into the final Y-shaped plan.