308 Royal Astronomical Sociely. 



II. Observations on the Appearance of the Comet of 1843, made 

 at Cape Coast Castle, on the Coast of Africa. By G. Maclean, Esq., 

 President of the Colony. Communicated by Captain Beaufort, R.N., 

 Hydrographer to the Admiralty*. 



The comet was first seen at Cape Coast Castle on the evening of 

 Friday, the 3rd of March, at about a quarter to seven. Part of its 

 tail only was then visible, bearing W.S.W., and making an angle of 

 about 70° with the horizon, towards the south. It was of the same 

 brightness throughout, and its breadth, which was little more than 

 a degree, so far as it could be seen on account of both extremities 

 being concealed by clouds, was also uniform. 



. March 4. — This evening the whole of the comet was visible, al- 

 though no nucleus could be distinguished. Its head, or what ap- 

 peared to be so, almost touched the horizon, near the star iota in the 

 tail of the whale ; and its tail extended about 22° from that point in 

 the direction of the constellation Columba Noachi. 



March 5. — Several glimpses of what appeared to be a nucleus were 

 perceptible through the telescope of a theodolite. It appeared as a 

 bright point, of the colour of Venus, but exceedingly small. Being 

 invisible through the telescope of the sextant, distances could not be 

 ascertained with any degree of precision. 



March 6. — The appearance of the comet was the same as the pre- 

 ceding evening. March 7, the brightness of the head and the length 

 of the tail were much increased, the latter extending upwards of 34° 

 in the direction of the constellation Lepus. Several stars were vi- 

 sible to the naked eye through the tail. On the 9th and 10th, the 

 appearance of the comet was much the same as on the 7th ; on the 

 17th it was visible, but the nucleus was very indistinct. The tail 

 extended about 43° in the direction of Sirius. 



March 19. — This night was clear, and the outline of the comet 

 very plainly marked. The bright spot or condensation in its head 

 was distinctly perceptible to the naked eye. On the 22nd, although 

 the sky was very clear, the nucleus was with difficulty perceptible, 

 from which it appeared that the comet was increasing its distance 

 from us with immense rapidity. The tail terminated midway be- 

 tween the stars ?, ij and 6 Leporis, and -x. Orionis. 



After this time the comet decreased in brightness and size every 

 night. Ou the 23rd its tail was about 38° in length ; on the 26th 

 about 35°, reaching a little past k Orionis. Through ordinary land- 

 glasses it still appeared as if there was a condensation of brighter 

 matter in the centre of the head. The comet continued visible on 

 clear nights till about the 10th or 12th of April, appearing as a thin 

 haze ; but after the 1st no observations could be taken with the 

 sextant. 



The following are the observed distances of the comet from Sirius 

 and Aldebaran. They are given without any correction, just as they 

 were read ofi" from the sextant ; and the observations were made 

 about seven in the evening. 



• For otiier observations of the comet of 1843 see Phil. .Mag. S. 3. 

 vol. xxiv. p. 522. 



