Speed of sound in water by a direct method

The speed of so und in distilled water wa,s m eas ured over the temperature ra nge 0 to 100 C with an acc uracy of 1 part in 30,000. The resu lts are given as a fifth-d egree polynomial a nd in tables . The water was contained in a cylindrical tank of fix ed leng t h, terminated at each end by a pla ne transducer, and the end-to-end time of flight of a pulse of so und was determined from a m easurement of t he pulse-repetition frequency required to set the success ive echoes into t im e coincidence.