FDC servicers William Siebold and Henry Hammelman knew each other in their home town of Buffalo, NY. Both ended up working in Washington, DC.; Siebold with the US Patent Office and Hammelman with the Post Office Department. Some of Hammelman’s earliest FDCs (1913) were addressed to Siebold and Siebold’s daughter, Marie, who was four years old at the time. Siebold would make his first FDCs in 1920 for the Pilgrim Tercentenary Issue (Scott 548-550). Some dealers confuse Siebold and Hammelman covers since both servicers addressed covers to the two Siebolds during the 1920s.
The Siebolds covers are each franked with 14-cents of stamps which cover the charge for double weight special delivery first class mail. The four-cent Grant envelope stamp is actually surcharged two cents (Scott U462).