New Windsor 19 Feby 1781.
I have directed B. Gen. Knox to have prepared at Philadelphia, with as much expedition as possible, a small battering train. He informs me that he shall send Lt Col. Stevens to Philadelphia for this purpose. I beg the favor that you will afford every assistance to Lt Col. Stevens which the means you may possess will admit, according to the orders given by General Knox.
The success of the expedition for which this apparatus is designed, may probably depend upon the secrecy of the preparations in Philadelphia. I have the honor to be Your most hum. servt
(signed) G. Washington
DLC: Papers of George Washington.