sentences:  By January 1923, the Coast and Geodetic Survey had decided to install a Hayes sonic rangefinder – an early echo sounder – aboard "Guide", which the Coast and Geodetic Survey planned to commission into its fleet later that year.It also decided to pursue the development of radio acoustic ranging, a new concept involving a method for determining a ship′s precise location at sea by detonating an explosive charge underwater near the ship, detecting the arrival of the underwater sound waves at hydrophones at remote locations, and radioing the time of arrival of the sound waves at the remote stations to the ship, allowing the ship′s crew to use triangulation to determine the ship′s position.Nicholas H. Heck (1882–1953), a United States Coast and Geodetic Survey Corps officer, took charge of that development process.