448 Observations on Donates Comet of 1858. 



The comet which has so recently visited us, and which has 

 now passed from view, was discovered by Donati at Florence, on 

 the 2nd of June 185S, in Right Ascension 9h. 25m. 12s., North 

 Polar distance 67 ° 13'. Its appearance was a round, bright, 

 nebulous patch of light, with a condensed centre, and without any 

 tail. It was seen at Berlin, by Bruhns, on the 7th of August : 

 and on the 23rd of the same month it was visible at Cambridge, 

 England. It was seen in Canada as early as the 6th or 7th of 

 September. On the 12th at 8 p. m., M. TV, its appearance was 

 bright and nebulous, the tail was slightly carved upwards, and it 

 was near the star Xi of the constellation Ursa Major, being 

 nearly in a line with the pointers Merah and Duhhe. Its position 

 (nearly*) was Eight Ascension lib. 20m., and North Polar dis- 

 tance 54° 23'. It was seen after sunset and before sunrise (which 

 led to the supposition of two distinct visible comets). Its appear- 

 ance gradually increased both in brightness and magnitude, until 

 the 10th of October. On the 28th of September, at S p. m., 

 its place was R. A. I2h. 32m., N. P. D. 57 ° 10'. Its tail extended 

 over nearly thirteen degrees, and was calculated to be about eighteen 

 millions of miles in length. It was then in the constellation Canes 

 Yenatici. On the 2d of October its R. A. was 13h. 30m., N. P. D. 

 66 z . Its tail was nearly twenty-seven degrees in length, curved 

 and reaching to Eta Ursa Major (Beuetnach). It passed over a 

 cluster of small stars in Coma Berenices, which were visible 

 through it. Its calculated distance from us was 50,000,000 of 

 miles, and its motion was at the rate of 20,000 miles per minute. 

 On the 4th of October it was near the bright star Arcturus, 

 and nearly rivaled it in brightness. On the lOth-llth of October 

 it passed from North to South Declination. On the 10th, at 

 6:30 M. T., its R. A. was 15h. 56m., and N. P. D. nearly 90 ° . 

 It was now at its maximum of brightness, and was a most 

 brilliant and magnificent spectacle. Its tail was nearly 5 ° in 

 length, curved like a Turkish sabre, and passing upwards through 

 the constellation Ojohiuchus, the star Phi of that constellation 

 apparently bounding its concave edge. Its convex border was 

 much brighter and better defined than its concave ; it extended 

 upwards nearly as far as Zeta Herculis. It crossed the Earth's 

 path on the 18th, and was nearest the planet Venus on the 

 morning of the 18th. 



* The measurements are taken only approximately from stars in its 

 neighborhood. 



