At three o’clock the general alarm was sounded. The Diesel engines were stopped and the engine clutch thrown out. We then shifted to our electric motors, which are always used for the submerged run. All outboard openings, such as the engine exhausts and ventilating systems, were closed. The conning-tower hatch was closed and secured. The Kingston sea-valves were opened, flooding the six ballast tanks, and the ship slowly submerged. We were then in a state of approximate neutral buoyancy—that is, neither heavier nor lighter than water. The Captain, who was at the periscope, keeping an eye out for any approaching vessels, gave the order: “Depth twenty-eight feet.” The diving officer, noting that more “rise” than “dive” rudder was being used, ordered four or five hundred pounds of water pumped from the adjusting tank to sea. This helped, but we were still a little heavy forward. By pumping water from the extreme forward tank to the extreme after tank, a proper balance or trim was obtained. She now held her depth easily. But to get a fine check, it was necessary to slow down to a very low speed, so that after a few more small adjustments of water, the ship would almost hang at any depth with very little rudder. As soon as the Captain saw that the diving officer had his trim, he lowered the periscope and ordered different depths and speeds to give the diving-rudder men practice at depth-keeping. Finally we reached one hundred feet. Everything went smoothly, so the Captain decided to come up. As we had been considerably below periscope depth for some time our motors were stopped and the hydrophone man trained his listening tube all around to see if there was any propeller noise from ships in the vicinity. Hearing none, the ship was brought rapidly to the surface by blowing the water from the ballast tanks, and soon we were cruising ahead again on our engines, Pensacola-bound. [Illustration: The ship was brought to the surface, and soon we were cruising ahead again, Pensacola-bound.] Word was passed shortly before eleven next morning to “rig ship for diving.” We had just about completed our full-power engine run and were preparing for our full-power run submerged. According to the rules, the dive on this run must be a crash dive, with a penalty applied against our yearly engineering standing if we did not get our conning-tower under water and out of sight in less than sixty seconds after the diving siren was sounded. A good diving crew could make it in considerably less time, but even with sixty seconds, each man had to know his job and do the right thing at exactly the right time. The ship was rigged for diving; the crew was standing by diving stations, and all was in readiness for the diving alarm which was to be sounded at eleven sharp. There was a feeling of alertness in the air. Everyone kept glancing at the clock.