Friday, June 24, 1864
Private Oliver Stanton Bates of Company A was severely wounded today at Petersburg. Oliver was struck in his left leg by shrapnel from an exploding Confederate shell while serving on picket duty .
He was transported to the field hospital at City Point where his left leg was amputated at the knee joint by Second Division Chief Surgeon Nathan Hayward.
1Compiled service record, Oliver S. Bates, Pvt., Co. A, 20th Massachusetts Infantry; Carded Records, Volunteer Organizations, Civil War; Records of the Adjutant General's Office, 1780s-1917, Record Group 94; National Archives, Washington, D.C.