 They guarded railroads, did patrol duty in Washington DC, and even manned the defenses of the city during Jubal Early's raid against Fort Stevens in July 1864.During the war, more than 60,000 men served in the Corps in the Union army; 1,700 soldiers during the service in the Federal Veteran Reserve Corps, of whom 24 died in action.Several thousand also served in a Confederate counterpart, the "Southern Invalid Corps", although it was never officially organized into actual battalions.