Service cover

Service cover - Postal item sent on active service, bearing relevant postmarks, and often carried free of charge.

Figure 3. This cover should be saved intact because it is a Railway Mail Service cover canceled en route on a train. Click on image to enlarge.

Dockwra's Post: private postal service covering London and its suburbs established by William Dockwra; introduced his own distinctive postmark in 1680; used from 1680-82.

See also: Front, Used, Local, Definitive, Cancel