450 Clusters and Nebulce. 



comet-finder ; on the contrary, the director, Otto Strove, could 

 only satisfy himself that it was perceptible in the great achro- 

 matic of 14§ inches with a power of 150, by moving the tube to 

 and fro. — 1862, September 29th, it was very easily visible at 

 Poulkowa with two smaller instruments, and even the comet- 

 finder of about three inches aperture, which also shows some 

 nebulas considered to be very faint; extent being, in such 

 cases, according to Winnecke, the condition of visibility — a con- 

 clusion which we have certainly seen borne out in the instance 

 of No. 4 of our present list. 



These details, which, under other circumstances, might be 

 thought tedious, appear admissible in an inquiry, the result of 

 which may prove of very great interest ; and whichever side 

 may ultimately prove to be right, the object is certainly curious 

 enough to deserve a search. I was thus employed a little be- 

 fore the earthquake in the early morning of October 6 ; when, 

 as I had so far lost sight of the foregoing particulars, that the 

 utmost of my recollection was that of a large faint triangular 

 object, including in one corner one of the brighter Pleiades, 

 my result, if any, was likely to be tolerably unbiassed. On 

 turning the telescope upon the group with powers of 29 and 64, 

 though I probably should not have discovered it unknown, I 

 found it with ease, as a very ill-defined, but on the whole egg- 

 shaped haze, encompassing a brilliant star with its smaller but 

 rather brighter end. A defective comparison with a diagram 

 frustrated the identification of the spot on the following day ; 

 but on reviewing it, November 10, I found immediately that 

 the star was Merope, and the glow connected with it the 

 nebula in question. Students who wish to find it have only to 

 point the telescope, with a low power, to Alcyone, the lucida 

 of the Pleiades, readily distinguished by its beautiful appendage 

 of a triangle of little sparkling gems; then Merope will be 

 the next bright star sp, and the nebula will be seen encom- 

 passing it, and stretching away in feeble and diffused light 

 towards the s, a little p, its greatest extent being, from a 

 comparison with the field of my comet eye-piece, about 1 7', or 

 nearly the distance between Merope and Alcyone. Obscure as 

 this object is, it may possibly prove a most important witness 

 as to the existence of luminous matter in an unconcentrated 

 form. It does not, however, stand alone, oivthe inference, from 

 such disputed grounds, might appear very inconclusive. Two 

 oilier similar instances, as we have observed, are suspected, 

 and, strangely enough, in the same region; the best authenti- 

 cated being at 9* distance, nearly in 1 he direction of Aldebaran. 

 The student, though he would now look in vain for this 

 mysterious nebula, may be glad to see its data, as given by 

 I /Arrest and Auwers. 1852, October 11, discovered by Hind, 



