"Special and Secret Bureau of the War Department" . . "Confederate Secret Service" . . . . "1865" . . . "Secret agents from the Confederacy" . "Confederate Secret Service" . "network of secret agents" . "Confederate Signal Corps" . . . . . . . "Commissioner of Prisoner Exchange" . . . . "operatives" . "1861" . . . . "Confederate secret service" . . "Secret Service" . . "Torpedo Bureau" . . .