Lord Sandwich— By some intercepted letters which have just been communicated unto me by the secretaries’ office, I have not the smallest doubt that d’Estaing’s fleet is gone with Deane and Gérard¹ to attack either Philadelphia or New York. I think this so very material that without loss of time I transmit this intelligence unto you. Keppel, in his own paper, mentions that if certain intelligence arrives he must be authorized to detach.² I think, by the day I arrive at Portsmouth, we must receive some information of this; and if that is the case we must strengthen Lord Howe, for should his fleet and the army under his brother be destroyed, no one can answer what confusion it may not occasion at home.

I know very well, and I have with pleasure seen, every effort is used to fit out the fleet. I trust every vessel that can be hired or bought will be collected, to be fitted as frigates and small craft, which, from having been obliged to send of that kind everything we had to America, has crippled us in a most essential article.