Such in brief outline was Maury’s first cruise. Though none of his letters giving his impressions of these first months at sea have been preserved, yet it is not difficult to imagine with what eagerness and delight his active young mind observed the strange sights and assimilated the new experiences. Many years afterwards he wrote of how he secured a Spanish work on navigation in order that he might acquire a new language and a science at the same time. In this connection he related how he resorted to various artifices for study while on watch. “If I went below only for a moment or two,” he wrote, “and could lay hands upon a dictionary or any book, I would note a sentence, or even a word, that I did not understand, and fix it in my memory to be reflected upon when I went on deck. I used to draw problems in spherical trigonometry with chalk on the shot, and put them in the racks where I could see them as I walked the deck. That with so much perseverance I should have failed in my prime object, I attribute to the want of books and proper teachers in the navy”. It was this seriousness of purpose and industry that caused Maury soon to become well known among his shipmates for his scholarship, and the story is told that even on this first cruise a certain mathematical problem was passed from steerage to wardroom without solution until he solved it. After making a short visit to his home in Tennessee, Maury set sail on June 10, 1826 from Norfolk on the frigate _Macedonian_ to which he had been ordered for temporary duty. This ship was bound for Rio Janeiro where she arrived after a passage of sixty-two days. After cruising in Brazilian waters for awhile, the frigate went on down the coast to Montevideo. At this time a war was raging between Brazil and Argentina over Banda Oriental, or Uruguay, which had been a sort of political football between the two countries until 1821, when it was partly subdued by Brazil. In 1825, however, it rose against this empire, and after a long struggle of three years it succeeded in having its independence recognized by the treaty of Rio Janeiro, on August 27, 1828. This state of affairs constituted the principal reason why American ships of war were sent to those waters. Thus was Maury brought into touch with history in the making, and the letters which he wrote at this time show an alert interest in what he was observing and display as well an unusual ability in recording experiences and his impressions of the people.