a pharmacist to become a member of the American Pharmaceutical Association, listing Bayou Sara, Louisiana, as home in 1858. While still in New Orleans, Longshaw assisted the local medical community in combating a summer Yellow fever epidemic. After further study at University of Michigan Medical School Longshaw received his medical degree in 1859. His handwritten graduation thesis, still in the Michigan Historical Collections, is entitled "The Physiology of Fecundation". As a student, Longshaw was a clinical assistant to the professor of surgery; he was also granted "a special degree in chemistry, both qualitative and quantitative analysis." After obtaining his degree, Longshaw gained experience taking "charge of four wards of an Army hospital." On July 10, 1860, Longshaw embarked as surgeon of the polar expedition led by Isaac Israel Hayes which wintered that year on Ellesmere Island; Longshaw himself returned in November 1860, reporting temporary snow blindness. He reported that he and another crewman had witnessed a solar eclipse which occurred on July 18. Naval service USS Yankee Entering the Navy as an acting assistant surgeon June 25, 1862, Longshaw was described as a slim, fair-skinned fellow of average height with dark hair and gray eyes. Longshaw was assigned to , an armed paddle wheel tugboat which had seen action in Charleston Harbor, the evacuation of the Norfolk Naval Yard, and in the Potomac River basin. While Longshaw was in service on Yankee, the little gunboat served on the James River flotilla, supporting McClellan's Peninsula campaign. In July, Longshaw participated in a nighttime raid that captured two ships without firing a shot. In August 1862 Yankee returned to the Potomac to guard approaches to the nation's capitol. On August 14, Longshaw reported to the Philadelphia Naval Asylum for board examinations. Passing the Naval Medical Board examinations required not only a thorough medical knowledge of fields such as chemistry, anatomy, physiology, obstetrics and "principles and practice of surgery", but also a test of the candidate's "mental, moral and physical qualifications" necessary for arduous sea duty. Longshaw passed with 595 out of a possible 780 (76.2%) in about three days of testing. Still only an acting assistant surgeon, Longshaw returned to Yankee, serving until mid-October. Boston Navy Yard Longshaw was finally appointed assistant surgeon in November 1862 and was transferred to the receiving ship at Boston Harbor, waiting orders and assignment to his next vessel. Until March, Longshaw served as a medical officer