His duties and pleasures, did not, however, alienate him from the sweetheart of his boyhood, for he kept up as frequent and interesting a correspondence with Miss Ewing as he had done at West Point. In the summer of 1863 he got a leave of absence for three months and spent that time with her at Lancaster. In November of that year he set out to return to Charleston by way of New Orleans. Part of the way he travelled with Henry Stanbery, afterward Attorney General of the United States. At Cincinnati he spent some time with his two brothers, who were employed in the Gazette printing office. He spent a week at St. Louis, visiting the arsenal and Jefferson Barracks, and was much impressed with the future possibilities of the city, which then had only about 40,000 inhabitants.
So he returned to Charleston, and there he was a busy student, concerning himself chiefly with observations of the country from a professional point of view. Says Mr. Reid in his "Ohio in the War": "Nothing could more strikingly exhibit the foundations of that wonderful knowledge of the topography and resources of the South which was afterwards to prove so valuable, than this scrap of a letter to Philemon Ewing: 'Every day I feel more and more in need of an atlas, such as your father has at home; and as the knowledge of geography, in its minutest details, is essential to a true military education, the idle time necessarily spent here might be properly devoted to it. I wish, therefore you would procure for me the best geography and atlas (not school) extant.'" Writing from Fort Moultrie he said: "Since my return I have not been running about in the city or the island, as heretofore, but have endeavored to interest myself in Blackstone. I have read all four volumes, Starkie on 'Evidence,' and other books, semi-legal and semi-historical, and would be obliged if you would give me a list of such books as you were required to read, not including your local or State law. I intend to read the second and third volumes of 'Blackstone' again; also 'Kent's Commentaries,' which seem, as far as I am capable of judging, to be the basis of the common law practice. This course of study I have adopted from feeling the want of it in the duties to which I was lately assigned.... I have no idea of making the law a profession; but as an officer of the army, it is my duty and interest to be prepared for any situation that fortune or luck may offer. It is for this alone that I prepare and not for professional practice."
Soon after getting back to Charleston he was assigned to duty in the upper part of Georgia and Alabama, and on this errand he travelled over the region in which, many years later, he conducted one of his greatest campaigns. Thus he acquired knowledge which was afterward of incalculable value to him and to the National Government.
In the winter of 1844–45, he was on a deer hunting expedition on the Carolina coast, and got his right arm thrown out of joint by an accident. Being thus disabled he got a leave of absence and went North, going as usual to the centre of attraction at Lancaster. In March he returned to Fort Moultrie, just at the time when Congress provided for the annexation of Texas and war with Mexico was expected. He remained at Fort Moultrie, however, for some time longer. Charleston was then a proud, aristocratic city, and considered itself a most important place in the Union. There was already much talk about the right of secession and there were often angry controversies over the subject, even at the officers' own mess-tables. But Sherman at this time had no idea that such talk would ever go further than it had already gone in 1832–33, when "Nullification" was so promptly stamped out by President Jackson and General Scott.
In the spring of 1846 Sherman was at Fort Moultrie, under the command of Captain, afterward General, Robert Anderson. Among other officers there at the time were Henry B. Judd, George B. Ayres, William Gates, Martin Burke, E. D. Keyes, T. W. Sherman, H. B. Field and Joseph Stewart. George H. Thomas and John F. Reynolds had already gone on to join General Taylor's army in Texas. In April, Sherman was sent to Governor's Island, New York, and thence to the recruiting station at Pittsburgh, Pennsylvania. Soon after this he received authority to open a recruiting station at Zanesville, Ohio, to his great delight, for Lancaster and Miss Ewing were only thirty-six miles away.
When news arrived of the battles of Palo Alto and Resaca de la Palma he became much excited at the prospect of actual war and hurried back to Pittsburgh. There he found a letter from his friend Ord, then at Baltimore, saying that his company had just received orders to go to California and urging him to go also. Sherman at once wrote to the Adjutant-General, at Washington, D. C., applying for active service. Then, in his impatience and without authority, he left a corporal in charge of his office and hastened to Cincinnati. There he reported to Colonel Fanning, a veteran officer, and asked to be sent on to the front. But Fanning, instead of appreciating the young soldier's zeal, gave him a hearty scoring for leaving his post without orders, and told him to get back to Pittsburgh as quickly as he could. Sherman obeyed, but of course stopped off at Lancaster on the way. He arrived at Pittsburgh late in June and found there awaiting him an order relieving him from the recruiting service and assigning him to Company F, then under orders for California. He made up his accounts, turned over the balance of cash to the physician, and in a few hours was on his way to New York where his company was already aboard ship and ready to sail for California by the way of Cape Horn.
Sherman and his fellow officers went aboard on July 14th, 1846, and set off on their long voyage. The "Lexington" was an old ship, formerly a sloop of war but now a store ship. Sherman and Ord roomed together. On the voyage they drilled the men as thoroughly as possible. They amused themselves with various games, but no gambling was allowed. On "crossing the line" a few of the greenhorns were put through the usual ceremonies, but the officers were exempted. In sixty days they reached Rio Janeiro, where they had a jolly time for a week. Sherman's companion in his rambles about town was Lieutenant, afterward General Halleck. They saw the Emperor and his family. Their first supper in the city was a sumptuous meal and the bill footed up to 26,000 reis. This sum staggered them, until they found out that it meant only about $16.
From Rio they proceeded to Cape Horn, which they rounded in very rough weather, and in sixty days reached Valparaiso, where they remained ten days. About the middle of January they neared the California coast, which they had to approach cautiously because no trustworthy charts were then in existence. They made their landing at Monterey, and there learned that the Californians had broken out into an insurrection, that the fleet under Commodore Stockton was down the coast near San Diego, that General Kearney had been defeated in battle, and that the whole country was in a pretty bad plight. Accordingly they got their weapons into shape for immediate use and expected to begin fighting the moment they set foot on the shore. It was January 26th, 1847, when they dropped anchor in the bay of Monterey, after a voyage of one hundred and ninety-eight days from New York.