Genl Potters quarters [Radnor, Pa.] 22d Decr 1777-12 oClock

sir

A large Body of the Enemy are on their march to Derby, where they must have arrived by this time, the number uncertain, but you may rely are formidable, they certainly mean to forage where I mentioned in my Letter of Yesterday-at 8 this morning about 20 Dragoons of the Enemy came up to the Fox Chase, to give the alarm, & then took the route to Derby-I have alarmed Morgan-the Genl is rode out but is expected every moment-If a Corps was thrown instantly toward Middle ferry their retreat is inevitably cut off. I am in haste Your hble servt

Jno. Clark Jun.

I fear they've cau't a few of our Light Horse.