An autographed letter by Benjamin Franklin is to feature in Robert A Siegel's United States Postal History sale in New York on December 19-20, valued at $20,000-30,000.

It was written to a botanist friend named Humphrey Marshall in 1769.

The letter features the statesman's free frank, along with a discussion of his hope for a peaceful outcome to the sabre rattling between Britain and the US.

The letter also features a discourse on paint swatches: "I received your obliging Favour of April 13, with Specimens of the several colours suitable for Painting which you have found in different Parts of our Country."

"It gives me great Pleasure to see them, and I have shown them to many Persons of Distinction together with your Letter."

We have this Peter Force copy of the Declaration of Independence for sale.

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