In the fall of 1861, Sheridan was ordered to travel to Jefferson Barracks, near St. Louis, Missouri, for assignment to the 13th U.S. Infantry. He departed from his command of Fort Yamhill, Oregon, by way of San Francisco, across the Isthmus of Panama, and through New York City to home in Somerset for a brief leave. On the way to his new post, he made a courtesy call to Maj. Gen. Henry W. Halleck in St. Louis, who commandeered his services to audit the financial records of his immediate predecessor, Maj. Gen. John C. Frémont, whose administration of the Department of the Missouri was tainted by charges of wasteful expenditures and fraud that left the status of $12 million in debt. Sheridan sorted out the mess, impressing Halleck in the process. Much to Sheridan's dismay, Halleck's vision for Sheridan consisted of a continuing role as a staff officer. Nevertheless, Sheridan performed the task assigned to him and entrenched himself as an excellent staff officer in Halleck's view.