Founding Fathers Robert Morris and George Clymer Signers' Mulberry Pen # B;ATH11007This pen is from Signers' Mulberry, held to be the only still living tree planted by a signer, growing at Summerseat in Morrisville Pennsylvania. Summerseat was not only Washingtons headquarters for a time but also the home of two signers of the Declaration of Independence and the US Constitution Robert Morris and George Clymer. This two tone pen has beige concentric ovals on one side and is honey brown with dark knots on the other. This tree is