334 COSMOS. 



Outlines, 881.) This similarity to a dumb-bell entirely 

 disappeared in Lord Rosse's reflector of three-feet aperture.' 8 

 (See his recent important delineation. Philos. Transact, for 

 1850, pi. xxxviii. fig. 17.) It was also successfully resolved 

 into numerous stars ; which, however, continued mixed with 

 nebulous matter. 



The spiral nebula in the more northern of the Canes Venatia 

 was discovered by Messier on the 13th of October, 1773 (on 

 the occasion of his discovery of the Comet), in the left ear of 

 Asterion, very near ij (Benetnasch) in the tail of the Great 

 Bear (No. 51 of Messier, and No. 1622 of the great Cata- 

 logue published in the Philos. Transact, for 1833, p. 496, 

 fig. 25.) This is one of the most remarkable phenomena in 

 the firmament, both on account of its singular configuration, 

 and of the unexpected transformative effect produced on its 

 appearance by Lord Rosse's six-feet speculum. In Sir John 

 Herschel's eighteen-inch reflector, the nebula presented the 

 appearance of a spherical body, surrounded by a far distant 

 ring, so that it exhibited, as it were, an image of our 

 starry stratum with its galactic ring." But in the spring of 



1845, the large Parsonstown telescope transformed the whole 

 into a helicine twisted coil a luminous spiral, whose convo- 

 lutions appear unequal, and are prolonged at both extre- 

 mities, both in the centre and outwards, into dense, granular, 

 globular nodules. Dr. Nichol made a drawing of this object, 



w Compare pi. ii. fig. 2 with pi. v. in Thoughts on 

 some important points relating to the system of the world, 



1846, (by Dr. Nichol, Professor of Astronomy at Glasgow), 

 p. 22. " Lord Rosse," says Sir John Herschel, Outlines, 

 p. 607, " describes and figures it as resolved into numerous 

 stars with much intermixed nebula." 



17 Cosmos, vol. i. p. 141 and note, where the nebula, 

 No. 1622, is termed a "brother- system." 



