104 PHILOSOPHICAL TRANSACTIONS. [aNNO 1771, 



place where it was struck, with 3 fishes sporting round it ; and on the reverse a 

 horse's head, under which appears the inscription. It will be almost needless to 

 remark, that the horse's head is one of the most usual symbols on the reverses of 

 the ancient Carthaginian coins. 



XIII. On a New Comet, By M. Messier, of the Royal Acad, of Sciences, and 



F.R.S. Translated by Dr. Bevis, F.R.S. p. 104. 



M. Messier discovered a new comet, the 10th of Jan. instant. 1771, about 8 

 o'clock in the evening; it was between the head of Hydra and the Little Dog, 

 over the parallel of Procyon. The position of which he determined by comparing 

 it with that star, and the star S in Hydra. The observations are as follow : 

 (•The lOth of Jan. 1771, at 10" l6"' 45' true time. 



1st Obs. i Right Ascension of the Comet 121" 



L North Declination 5 



f Same night at 21 



2d Obs. < Right Ascension of the Comet 140 

 (.North Declination 6 



<■'- From which observation it appears, that in 3*^ 2" 20* of time, its motion in 

 right ascension was 1° 11' 45", and 43' 3]" in declination : this comet was per- 

 ceived by the bare eye. In the telescope its nucleus is bright, of a whitish com- 

 plexion, and not very well defined, surrounded with an atmosphere several 

 minutes wide, with a faint tail 5 or 6 degrees long. Its apparent motion among 

 the fixed stars is contraiy to the orda* of signs, from the equator towards the 

 north pole. ■]v^l^{^,^^^[n•0 y. 



This makes the 12th comet he discovered and observed in 13 years past. 



From his further observations, ■ M. Pingre deduced the following elements of 



its orbit : 



Ascending 8." '.'.^!'.'i". 3' 18° 42' 10" Place of the perihelion 8' 28° 22' 44" 



Indication of the orbit 3i 25 55 Log. of the perihel.dist 9.722833 



It passed the perihelion Nov. 22, 1770, at 22'' 5"" 48' mean time, at the royal 



observatory, motion retrograde. He adds, ' that the comet resembles none of 



those whose elements are determined on comparing its motion with the places of 



its perihelion and Q, : it is easy to see, that' it was impossible to discover it at 



Paris before the year 1771; and it ina;y even be added, that it must frequently 



have passed in the sun's neighbourhood, imperceptible to the northern parts of 



the earth.' 



XIV. Description and Use of a New Constructed Equatorial Telescope or Port- 

 able Observatory, made by Mr. Edward Nairne, London, p. 107. 



The instrument consists of the following parts: A mahogany triangular stand, 

 and 3 adjusting screws ; a moveable azimuth circle, which is divided into degrees, 

 and by a vernier index to every 6 minutes ; above this azimuth circle is the hori- 

 zontal plate, to the under part of which is fastened the vertical conical axis ; on 



