Dr Sr,
I have taken some pains to inspect the situation of Our Forts and Chevaux de frize, and do acquaint you as my Opinion that if some troops and Boats of Observation down the River is not [sent], you may Sune expect to here of the Enemy having Billings Port in Possession and your strength by water of no service, for one hundred men crossing at or below Chester at night [might] have it in Possession by morning and Command Your Batteries and what other Vessels may be stationed there, your other fort and Pass may be suprised by the Like Plan, and be Asured that they have their Servants amongst us, your city will much sooner be in their hands if Attention is not given to the Vessels by some Person of Knowledge. I am With much Respect [&c.]
Charles Alexander
Delaware Frigate off Billings Port Septr 15th, 1777.
1. Hazard, et al., eds., Pennsylvania Archives, 1st series, V, 626.