.322 THE EARL OF ROSSE’S OBSERVATIONS ON SOME OF THE NEBULAE. 
of observing- would have been quite incompatible with the constant care and atten 
tion required in the progress of the more important work, the construction of a 
telescope of greater power, so that much fewer objects have been examined than 
would otherwise have been practicable ; and even with the great facilities afforded 
by Sir John Herschel’s invaluable catalogue, the whole amount of work done has 
been no more than the examination of about two-thirds of the figured nebulse, and 
a few others in the general catalogue, many of them, or rather, perhaps, most of them, 
under circumstances but moderately favourable. 
The sketches were originally made in the gallery of the telescope, and represent 
the objects placed as they appeared, not as they actually exist in space. I have 
copied them without alteration, not. thinking that anything would be gained by 
placing them approximately in their true positions, while they would perhaps be less 
convenient for future re-examination and correction. The references are to Sir John 
Herschel’s Catalogue. 
Plate XVIII. fig. 88 is one of the many well-known clusters; I have selected it 
merely for the purpose of showing that in such objects we find no new feature, nothing 
which had not been seen with instruments of inferior power ; the stars, of course, are 
more brilliant, more separated, and more numerous. I fear that no amount of optical 
power will make these objects better known to us, though perhaps exact measurements 
may bring out something. 
Fig. 81 is also a cluster; we perceive in this, however, a considerable change of 
appearance ; it is no longer an oval resolvable Nebula ; we see resolvable filaments 
singularly disposed, springing principally from its southern extremity, and not, as is 
usual in clusters, irregularly in all directions. Probably greater power would bring 
out other filaments, and that it would then assume the ordinary form of a cluster. 
It is studded with stars, mixed however with a nebulosity probably consisting of stars 
too minute to be recognized. It is an easy object, and I have shown it to many, 
and all have been at once struck with its remarkable aspect. Everything in the 
sketch can be seen under moderately favourable circumstances. 
Plate XIX. fig. 26, on the contrary, is a difficult object; it requires an extremely 
fine night and a tolerably high power ; it is then seen to consist of innumerable stars, 
mixed with nebulosity; and when we turn the eye from the telescope to the Milky 
Way, the similarity is so striking that it is impossible not to feel a pretty strong 
conviction that the nebulosity in both proceeds from the same cause. 
Fig. 29. — The annular nebula in Lyra; 2 is the star in Sir John Herschel’s 
sketch ; I have inserted the six other stars as in some degree tests of the power of a 
telescope. Near star 3 there are two very minute stars seen with great difficulty ; the 
others are easily seen whenever the night is sufficiently good to show the nebula 
well. The filaments proceeding from the edge become more conspicuous under in- 
creasing magnifying power within certain limits, which is strikingly characteristic of 
a cluster; still I do not feel confident that it is resolvable. I am however disposed to 
