Wouldn't it be great to have an organizational chart listing all medical officers at the different hospitals and military posts?
Documents like the discharge are indirect evidence in contrast to service files of the medical officers mentioned. They may also be mentioned in the Official Records and Southern Historical Society papers (SHSP has a lengthy entry on Confederate physicians). You may also find notices in newspapers about these hospitals and their staffs.
The 1st Alabama Regiment, formerly a twelve-month organization, reorganized in mid-March 1862 as an artillery command. Despite the reorganization, all service records have been filed as if it was still the same infantry regiment. Most oficers and men surrendered at Island Ten on April 8, 1862.
Service records of Surgeon Jackson Decatur Caldwell include an order reassigning him to Okolona MS on March 15, 1862.