Are rare: - 30 of the November Leonids give a mean height of 842 to 572 m.
Per second, while the swifter class (meeting the earth like the Leonids of November) have a velocity of about 44 m.
His great contribution to astronomy dates from 1866, when he showed that meteors or shooting stars traverse space in cometary orbits, and, in particular, that the orbits of the Perseids and Comet III., 1862, and of the Leonids and Comet I., 1866, were practically the same.
The great meteor shower of 1866 turned his attention to the Leonids, whose probable path and period had already been discussed by Professor H.
In 1867 the remarkable discovery was made that Tempel's comet (1866: I.) revolved in an orbit identical with that of the Leonids.