Payoff --- Diver John Reaves of Sealab-II project, rewards porpoise Tuffy with a fish as they train together 80 feet down in the open ocean off Point Mugu, Calif. Tuffy will work with Reaves and other divers next month in experiments to see how a porpoise can assist man underwater. A snap hook is attached to Tuffys harness which enables him to carry messages and tools to the divers. Sealab-II, a joint effort of the Office of Naval Research and the Navys Special Projects Office, will subject divers to long periods of living and working underwater. Tuffy will join the Sealab-II team for about a week early in September. The experiments with Tuffy during Sealab-II is a project of the U.S. Naval Missile Test Center, Point Mugu, Calif. Scientists there are studying marine mammals in the hope of obtaining information which will enhance mans operations underwater. Photograph taken on 13 August 1965.