Aerial Photo for Trego County, location T ? S, R 21-22 W, project GS-CGZ. Date of photo 1938-10-20. Range of sheets "32: 37-55, 33: 120-156, 77: 29-47, 34: 193-208, 118-114, 100, 35: 44-59, 74: 227-223". Number of sheets 115. Photo is located at T ? S, R 21-22 W