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132 to his friend Admiral Smyth, Mr. (afterwards Sir Thomas) Maclear said:—

So far as I know this is the only account which has ever appeared in print, written by one who had had the chance of seeing both comets, and was capable of scientifically appraising them. Sir John Herschel would have seen all three of these bodies (1811, 1843, 1858), but he does not appear to have left behind him any remarks on the earliest one. This may not be extraordinary, seeing that he was only an Undergraduate at Cambridge, and only aged 19 when the comet appeared, and that he did not start his astronomical career until 5 years afterwards. The Comet of 1843 was first seen in the Southern Hemisphere in the last week of February, but nobody can be named as its first discoverer, because it displayed itself suddenly, and was seen by a multitude of persons. During the first fortnight in March it shone with great brilliancy, and the journals of Australian and New Zealand colonists make many allusions to it. It was not visible in England until after March 15, when its splendour had much diminished, but the suddenness with which it made its appearance to observers in the Northern Hemisphere, as it had done in the Southern, added not a little to the interest which it excited. The general length of the tail during March, as seen in the Northern Hemisphere, was about 40°, and its breadth about 1°.

The orbit of this comet is remarkable for its small perihelion distance, which according to the most trustworthy calculation did not exceed about 500,000 miles; and the immense velocity of the comet in its orbit when near perihelion occasioned some extraordinary peculiarities. Thus, between February 27 and February 28 it described upon its orbit an arc of no less than 292°. Assuming its true orbit to be elliptical, as we are entitled to do, this would leave