Washington DC: U. S. Government Printing Office, 1940. Presumed First Edition, First printing thus. Wraps. 525, [1] pages. Illustrations (some fold-out). Formulae. Outline of Instruction Courses. Index. Changes No. 1, 4 pages, laid in--with frayed edges. Change No 1. has Figure 20.1--Surveying Altimeter. Issued in 1944. Cover has some wear and soiling. The matter contained herein supersedes TR 190-35, March 16, 1925; TM-2180-30, February 18, 1929; TM 2180-35, January 3, 1928; TM 2180-45, April 16, 1928; TM 2180-60, March 1, 1928; and TM 2180-61, July 15, 1927. "1. Purpose and scope. — a. Purpose. — This technical manual is intended to provide, in single text form, detailed directions for the care, use, and adjustment, of surveying instruments, together with step-by-step descriptions of practical and modern methods applicable to military survey activities. It is also intended to provide instruction in the utilization and exploitation of aerial photographs in connection with military mapping. More