SHERMAN, William Tecumseh (1820-1891). Autograph letter signed ("W. T. Sherman Maj G Comdg") to Major General James B. McPherson, "Head Qrs, 15 Army Corps, Camp on Big Black [River]", 4 September 1863.

Three pages, 246 x 198mm, bifolium. Housed in a custom clamshell case.

Sherman orders a tightening of security around Vicksburg by enlisting the services of former slaves. Sherman sends McPherson at Vicksburg detailed instructions on bolstering fortifications surrounding the critical Mississippi port town which had fallen to the Union on 4 July 1863. He advises the general that "A Batch of Negros have collected at Roach's Plantation on the Valley Road near the Baldgrand Creek. I authorized Gen C—— to be in command at Oak Ridge, & will renew to Gen Buckland the same instructions, to organize the males of that gang into a kind of outlying picket, giving them a few mules to grind the corn which abounds there, and giving them a little Bacon. There are about 100 Negros fit for service...." Sherman continues his instructions on fortifications and pickets and concludes by requesting that he restrict the distribution of "passes out of our Lines," fearing that too liberal a policy would lead "to a system of spies otherwise.