The Navy named the ship after James S. Chambers. He was appointed Navy agent for the Port of Philadelphia on August 10, 1861, by U.S. President Abraham Lincoln. He was already a co-owner and editor of the Philadelphia Bulletin. In 1860, one partner sold out and, with increased ownership, the co-owners voted Chambers publisher, a position he held at least as late as 1878. Chambers was an unabashed support of Lincoln not only due to his own position as Navy agent but also because his aged father had been made superintendent of warehouses for the Philadelphia customs service.
The schooner sailed from Philadelphia 6 days later and joined the Gulf Blockading Squadron at Ship Island, Mississippi, 23 January 1862. Her diligent service in the Gulf of Mexico and off the Florida coast was first rewarded on 23 August when she captured blockade-running schooner Corelia with a cargo of supplies badly needed by the South. Two days later she took Confederate steamerUnion attempting to escape with a cargo of 350 bales of cotton.
''James S. Chambers'', a "vigilant blockader"
James S. Chambers scored again on 4 March 1863—the second anniversary of President Abraham Lincoln's inauguration—when men from her whaleboats boarded and took Spanish sloop Relampago with a cargo of coffee, liquors, and soldiers shoes. The triumph was capped late that afternoon when a sail was sighted to the south standing in for land. The unidentified ship ignored a shot across her bow and continued to race for the beach without showing any colors. The Union schooner continued the chase firing at her quarry until she ran aground. The following morning men from James S. Chambers boarded the wreck, a schooner of pilot boat-build, and identified her as Ida. They removed several boatloads of cargo before setting her afire. A final prize came on 18 June 1863 when the vigilant blockader captured schooner Rebekah.
Continued Florida operations
A period of almost a year's blockading duty stationed at West Pass, St. George's Sound, Florida, ensued. On 12 May 1864 boats from James S. Chambers and drove off a body of Confederate sailors embarking on a boat expedition ordered to capture the Union's side-wheel steamer.
In August 1864 James S. Chambers encountered a new enemy -- yellow fever. The epidemic forced her to return to Philadelphia after taking the lives of 13 sailors and 3 officers. Only two or three members of her crew escaped the disease.