Perry arrived at Vera Cruz in the _Mississippi_, March 20, 1847, after a passage of thirteen days from Norfolk. He was back just in time. Steam had enabled him to be on hand to accomplish one of the greatest triumphs of his life. His orders required him to attack the sea fort fronting Vera Cruz, “if the army had gone into the interior.” The United States fleet had lain before it for a whole year without aggression. He found our army landed and Vera Cruz invested on every side. The Mexicans were actively firing, but as yet there was no response from our side. That night it blew a gale from the North. The vessels hidden in spray, and the camps in sand, waited till daylight. Early next morning, March 21, Perry was informed that the steamer _Hunter_ together with her prize a French barque, the _Jeune Nelly_, which had been caught March 20th running the blockade out of Vera Cruz, and an American schooner, were all ashore on the northeast breakers of Green Island. Their crews, to the number of sixty souls, were in imminent danger of perishing. Among them was a mother and her infant child. Perry was quick to respond to the promptings of humanity. In such a gale, not a sailing vessel dared leave her moorings. The _Mississippi_ had parted her cables, owing to the violence of the wind. A British war steamer lay much nearer the scene of disaster, without apparently thinking of the possibility of moving in such a gale; but Perry knew his noble ship and what to do with her. He dashed out in the teeth of the tempest and forced her through the terrific waves. In admiration of the act, Lieutenant Walke made a graphic picture of the rolling _Mississippi_, which now hangs in the hall of the Brooklyn Lyceum. Reaching Green Island, Perry cast anchor. Captain Mayo and four officers volunteered to go to the rescue of the wrecked people. In spite of the great peril, they saved the entire party. The scene was one of thrilling interest when the young mother embraced husband and child in safety on the deck of the noble steamer. Had not the _Mississippi_ and Perry been at hand, the whole party must have perished. It was on his return from this errand of humanity that Commodore Matthew Perry was given and assumed the command of the American fleet—the first of such magnitude, and the greatest yet assembled under the American flag. The time was 8 A. M. March 21st. As Captain Parker recollects: “On the twenty-first of March shortly after the hoisting of the colors, we were electrified by the signal from the flag-ship ‘Commodore Perry commands the squadron.’” At once, Perry called with Conner upon General Scott concerning the navy’s part in the siege. The order of relief to Commodore Conner dated Washington March 3, 1847, was worded: “The uncertain duration of the war with Mexico has induced the President to direct me no longer to suspend the rule which limits the term of command in our squadrons in its application to your command of the Home Squadron.”