An Extract of a Letter from Abbé De la Caille, F. R. S. and Member of the Royal Academy of Sciences at Paris, to Matthew Maty, M. D. and F. R. S.

LVI. An Extract of a Letter from Abbé De la Caille, F. R. S. and Member of the Royal Academy of Sciences at Paris, to Matthew Maty, M. D. and F. R. S. Paris, Feb. 18, 1760. Read March 6, 1760. I'LL venture to send you some of my observations on the present comet, because bad weather may have prevented it from being seen in England. | Equal time | Longitude | North latitude | |------------|-----------|----------------| | Feb. 8 | 9 29 28 | 3 26 42 | | | 8 48 50 | 4 46 28 | | 11 | 7 22 35 | 7 14 50 | | 13 | 7 47 4 | 8 24 18 | | 14 | 6 41 0 | 10 30 9 | These observations, together with another made at Marseilles, (on the first day) at $9^h\ 55'\ 38''$ equal time, when the longitude of the comet was found in $\Omega\ 23^\circ\ 29'\ 46''$, and its north latitude $31'\ 20''$, have enabled me to compute the elements of its orbit. Its motion is direct. The ascending node is in $\Omega\ 19^\circ\ 42'\ 0''$, and the place of the perihelion in $\varpi\ 26^\circ\ 41'\ 22''$. The inclination of the orbit is $80^\circ\ 51'\ 30''$, and the distance of the perihelion $\frac{85248}{100000}$ of the radius of the orbit of the earth. The comet passed the perihelion Nov. 25, 1759, at $20^h\ 55'$, mean time, at Paris. These computations will be further improved by the observations I still hope to make; but they are sufficient to find the comet's place in the heavens. Vol. LI.