Qualifications
Those serving in the Invalid Corps were divided into two classes:
Class 1, partially disabled soldiers whose periods of service had not yet expired, and who were transferred directly to the Corps, there to complete their terms of enlistment;
Class 2, soldiers who had been discharged from the service on account of wounds, disease, or other disabilities, but who were yet able to perform light military duty and desired to do so.
As the war went on, it proved that the additions to the Corps hardly equalled the losses by discharge or otherwise, so it was finally ordered that the men who had had two years of honorable service in the Union Army or Marine Corps might enlist in the Invalid Corps without regard to disability.
The soldiers shown in the rosters of the 15th Massachusetts Volunteer Infantry (where they originally enlisted) and who then transferred to the V. R. C. belong to Class 1.