278 Nebulce. 



is 3 — 4' long, V broad, and with a darkness in the middle, so 

 as to convert it into a double nebula, of which the n p portion 

 is the brighter, and the axis inclined 20° to the parallel. The 

 other nebula is : 



34. Gen. Cat. 4415. E.A. xviiih. 23m. 35s. D.N. 71° 

 30' 12". Discovered by Tuttle (America) 1859, Sept. 1. The 

 possibility of variation here had already been pointed out by 

 H. on a ground repeated by Kiimker, namely, that D' Arrest 

 had seen it in a comet-finder, 1862, Sept. 24, so large and so 

 bright, that in a similar condition it could not have escaped M., 

 Ijl., or H. When we bear in mind the insufficiency of M/s 

 optical means, which led him to assure himself that the glo- 

 rious nebula in Hercules contained no stars, the brightness, in 

 1862, of an object which, in the opinion of so great an autho- 

 rity as D' Arrest, could not have escaped his notice, is very 

 striking. We must not, however, forget that the great light 

 and expanded field of a comet-finder would give it a very dif- 

 ferent aspect. When observed by Biimker, 1866, Oct. 4, 5, 

 6, 7, it was entered as pretty faint, or only moderately bright, 

 and he remarks that, in the field of an ordinary comet-finder, 

 it would have been seen with great difficulty, or only in con- 

 sequence of its juxtaposition with two 11 mag. stars p. at a 

 short distance. It would be an interesting object of study. 



To these we shall add two others, not very distant from 

 the region of our red star, which we must look for with little 

 delay, in consequence of their small meridian altitude and the 

 advancing season. 



35. The Gaseous Nebula in Hydra. Gen. Cat. 2102. Ijl. iv. 

 27. Sm. describes this as a pale, greyish- white, planetary 

 nebula, resembling Jupiter in size, equable light (not, of 

 course, brilliancy) and colour, with four telescopic stars sur- 

 rounding it, a line between those wp and sf touching the disc 

 — a not unimportant remark, from the suspicions which have 

 been entertained of the possibility, either of satellite-stars, or 

 proper motion in nebulous masses. IT., who includes it as 

 No. 3248 in his S. catalogue, says it extends about 30" by 25", 

 and is of a very bright, uniform light, and very decided pale 

 blue colour, but not quite sharp at the edges. In 1851, with 

 an aperture of 3yVinch.es, I found it a very bright and beau- 

 tiful object, so small with 64 that it might be overlooked in 

 sweeping, but bearing increase of power wonderfully up to 

 250 ; the elliptical form, the haziness of the limb, and the blue 

 tint, were all independently noticed ; which is simply worthy 

 of mention as an encouragement to the possessors of the 

 smaller class of instruments. I now see it (1867, April 9) 

 with the 9 T J -inch mirror, as a very brilliant object ; and the 

 effect of increase of aperture is strikingly exemplified in its 



