 "Proprietary" and "Documentary" stamps often bore these respective designations, while in several of the issues they shared the same designs, sometimes with minor variations.Beginning in 1862 the first revenue stamps were issued, and would continue to be used for another hundred years and more.For the first twelve years George Washington was the only subject featured on U.S. revenue stamps, when in 1875 an allegorical figure of "Liberty" finally appeared.