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supposing that you Gentlemen have received it. The latitude of Selenginsk is 51d6′6″. I have settled the longitude to be 6h57′50″ from the Paris meridian. Some immersions of the first and second satellite of Jupiter have given me 6h57′15″, 6h57′20″, and 6h58′31″, by comparing the observations of Mr. Rumowski with the tables corrected upon the observations made at Paris and at the Cape, and estimating, as well as I was able, the different effects of the reflectors and telescopes. The 15th of July, Mr. Le Monnier observed the meridional transit of φ Sagittarii at 18h25′38″ 23 of his clock, being at 76°00′45″ from the zenith. The preceding limb of the Moon passed at 18h38′28″ 12, or at 11h01′40″ apparent time; when the center passed, the distance of the upper limb was at 75d52′00″ from the zenith; and the lower at 76d22′25″; the threads, which are 5″ thick, being entirely upon the Moon. σ Sagittarii had passed at 18h35′22″12, the distance from the zenith being 75d22′20″. I have observed at Rodriguez the immersion of σ Sagittarii at 14h01′28″12 apparent time, and Mr. Rumowski observed at Selenginsk the immersion of φ at 11h24′51″ apparent time. Upon comparing all these things together, I find the longitude of Selenginsk to be 6h57′21″12 East from Paris. But this goes upon the supposition that the error of the tables has been quite constant during near 7 hours, which cannot be warranted. Lastly, the observation of the eclipse of the Sun made at Selenginsk June 3; 1761, compared with the same observation made at Tobolsk and at Cajanebourg, determines the longitude of Selenginsk 5h16′41″12 East from Cajanebourg, and at 2h34′30″ East from Tobolsk, consequently 6h58′22″
