Nebula. 187 



more S., as having " a pretty bright milky nebulosity equally 

 dispersed all round it," which he calls " a very remarkable 

 phcenomenon." He numbers it 45 of his IVth Class, i.e., 

 that of Planetary Nebulce. In the earlier catalogue of Herschel 

 II. (1833), where it stands No. 450 (it is 1532 of the General 

 Catalogue), it is termed c< a star 8m. exactly in centre of an 

 exactly round bright atmosphere 25" diam. The star is quite 

 stellar, not a mere nucleus. Another star 8ni. distant 100", 

 and about 85° np, has no such atmosphere. A most remark- 

 able object/ 7 The Earl of E-osse calls it " most astonishing," 

 and represents it as a star surrounded at some little distance, 

 rather nearer perhaps on the np side, with a bright nebulous 

 ring, within which again is a less luminous area, brightening 

 up as it approaches the star near its centre ; leaving, however, 

 a small dark space close to the star on the /side. This curious 

 object does not require a large instrument to bring out all its 

 interest. I have seen it formerly, on two occasions, with S-f^ 

 inches of aperture, as a small telescopic comet. 1864, Dec. 1, 

 on looking for it with 5-£ inches I caught it with about 30, 

 and saw the central star with 65. The haze, I found, bore 

 magnifying well (whence Ijl probably gave it its planetary 

 rank) ; it appeared slightly more extended s a little /, and with 

 451 there seemed to be a very feeble trace of a narrow border 

 of greater brightness at the edge in that one direction, some- 

 thing like a cometary envelope. At this time I had so indis- 

 tinct an idea of what Lord Rosse had seen, that my observation 

 may be fairly considered an independent one.* The most 

 striking thing, however, that I noticed, was the angle of 

 position with the neighbouring 7-±- mag. star. This was given 

 by Sm., 1836-22, = 355°, identical with H's angle, 1833, de- 

 nominated by the quadrant, as was his practice at that time. 

 I had no micrometer or cross wires in the field, but a simul- 

 taneous view of Polaris with the left eye, and in four eye- 

 pieces, gave the line joining the stars an inclination below the 

 pole of about 5°, consequently bringing it out of the n p into 

 the nf quadrant. 



With very little reason, generally speaking, to trust to 

 my own estimates, all the circumstances of this case induced 

 me to feel unusual confidence in my result ; and I was much 

 more gratified than surprised when Mr. Knott obliged me 

 with a very full and careful set of measures with his 7j inch 

 object-glass, the mean of which gave for 1864*97, 100""2. 



* I have since found that Lassell also has figured it much in the same way» 

 but making the bright annulus very feeble on the p side, reducing the interior 

 darker area to a narrow ring, and omitting the dark spot close to the star. He 

 says, " The dark circle is very striking, and altogether the object is very beautiful 

 and interesting." 



