Since I had the honor of writing to your Excellency, on the 25th ultimo, the enemy have withdrawn their forces from the north side of James river, and have taken post at Portsmouth, which, we learn, they are fortifying. Their highest post is Suffolk, where there is a very narrow and defensible pass between Nansemond river and the Dismal Swamp, which covers the country below, from being entered by us. More accurate information of their force, than we at first had, gives us reason to suppose them to be from twenty-five hundred to three thousand strong, of which, between sixty and seventy are cavalry. They are commanded by General Leslie, and were convoyed by the Romulus, of forty guns, the Blonde, of thirty-two guns, the Delight sloop, of sixteen, a twenty-gun ship of John Goodwick’s, and two row-galleys, commanded by Commodore Grayton. We are not assured, as yet, that they have landed their whole force. Indeed, they give out themselves, that after drawing the force of this State to Suffolk, they mean, to go to Baltimore. Their movements had induced me to think they came with an expectation of meeting with Lord Cornwallis in this country, that his precipitate retreat has left them without a concerted object, and that they were waiting further orders. Information of this morning says, that being informed of Lord Cornwallis’s retreat, and a public paper having been procured by them, wherein were printed the several despatches which brought this intelligence from General Gates, they unladed a vessel and sent, her off to Charleston immediately. The fate of this army of theirs hangs on a very slender naval force, indeed.