SIR,--I have been honored with your Excellency's letter of the 8th instant. Having found it impracticable to move, suddenly, the whole Convention troops, British and German, and it being represented that there could not, immediately, be covering provided for them all at Fort Frederick, we concluded to march off the British first, from whom was the principal danger of desertion, and to permit the Germans, who show little disposition to join the enemy, to remain in their present quarters till something further be done. The British, accordingly, marched the 20th instant. They cross the Blue Ridge at Rock Fish Gap, and proceed along that valley. I am to apprise your Excellency, that the officers of every rank, both British and German, but particularly the former, have purchased within this State some of the finest horses in it. You will be pleased to determine, whether it be proper that they carry them within their lines. I believe the Convention of Saratoga entitles them to keep the horses they then had. But I presume none of the line, below the rank of field officers, had a horse. Considering the British will be now at Fort Frederick, and the Germans in Albemarle, Alexandria seems to be the most central point to which there is navigation. Would it not, therefore, be better that the flag vessel, solicited by General Phillips, should go to that place? It is about equally distant from the two posts. The roads to Albemarle are good. I know not how those are which lead to Fort Frederick. Your letter referring me to General Green, for the mode of constructing light portable boats, unfortunately did not come to hand till he had left us. We had before determined to have something done in that way, and as they are still unexecuted, we should be greatly obliged by any draughts or hints, which could be given by any person within the reach of your Excellency. I received advice, that on the 22d instant, the enemy's fleet got all under way, and were standing towards the capes: as it still remained undecided whether they would leave the bay or turn up it, I waited the next stage of information, that you might so far be enabled to judge of their destination. This I hourly expected, but it did not come till this evening, when I am informed they all got out to sea in the night of the 22d. What course they steered afterwards, is not known. I must do their General and Commander the justice to say, that in every case to which their attention and influence could reach, as far as I have been well informed, their conduct was such as does them the greatest honor. In the few instances of wanton and unnecessary devastation, they punished the aggressors. I have the honor to be, Your Excellency's most obedient humble servant. TO EDWARD STEVENS. RICHMOND, November 26, 1780.