LANGDON, John (1741-1819), Signer, U.S. Constitution.. Autograph letter signed ("John Langdon"), to Wharton & Lewis, Portsmouth [N.H.], 10 April, 1799. 1 page, 4to, integral address leaf, seal tear and stain, otherwise fine. A brief letter addressed to merchants in Philadelphia regarding the payment of a debt: "Enclosed is a draft of my Brother's for you for three hundred dollars, which you will please, pass to my credit." Langdon, a merchant from New Hampshire, served in the Continental Congress, was a delegate to the Constitutional Convention, served as Senator from 1789 to 1801, and was Governor of New Hampshire. Langdon ALsS are uncommon.