When I wrote to your Excellency the letter accompanying this, I designed to have sent it by Col: Laurens; but the Alliance sailed sooner than I expected, and I was consequently disappointed. Having now a direct opportunity from Beverly to Bil-boa, I improve it, to send to Paris by that route. Your Excellency would greatly oblige the American Academy, as well as me, by procuring a safe conveyance for the letters to London, which are enclosed to Dr Price. I am desirous of determining the longitude of Cambridge from Paris or Greenwich, by corresponding observations of so-lar eclipses, which you are sensible, Sir, are more to be depended upon for this purpose, than observations of the eclipses of Jupiter's satellites. I have yet got but one observation of a solar eclipse made at the Royal Observatory at Greenwich, corre-sponding with a Cambridge observation; and that was Augst 5th 1766. If your Excellency has opportunity, I should be extremely obliged to you to procure for me the observations of that eclipse, made at the Royal Observatory at Paris, and also of the eclipse of June 24th 1778, together with the beginning of the eclipse of April 23d the current year; which it is probable will be made there by the time you receive this letter. I am your Excellency's most humble & most obedient servt