NATORE 
regularity or peculiarity of arrangement that the idea 
of optical concurrence seems inadmissible. Triangles, 
squares, rhomboids, wreaths, festoons, coronets, indicate 
a collocation utterly inscrutable, but certainly not for- 
tuitous. Such combinations are occasionally met with 
in other regions; but, as might be expected, are accumu- 
lated in the galaxy. 
The glory of this sparkling zone, culminating in the 
splendours of Cygnus, is everywhere repeated in greater 
or less degree. Aguzla, Sagitta, Vulpecula, Lacerta, to 
say nothing of more distant regions, all present fields of 
most gorgeous richness, which we must leave unnoticed. 
But before we finally cross this region to the other side, 
we must pause in Vw/pecula, where, in R.A. 19h. 54m. 
D.N. 22° 23’, lies an especial mystery, the Dumb-dell 
Nebula (M 27). The search with the altazimuth will 
prove not difficult as guided by Diagram 2. 
In mid-distance between 8 Cyguz and a Aguile we 
we shall recognise a lengthened group of 4th and 5th 
mag. stars, the lowest in the figure, forming the constella- 
tion Sagitta. We may remark, in passing, that one of 
these, ¢, R.A. 19h. 44m., D.N. 18° 51’, is a very pretty 
wide double, the largest of which has been found by 
Alvan Clark, jun., to be an excessively close pair. Nearer 
to B Cygnz, but to the left, is another less marked group, 
forming part of Va/pecula, close to one of the stars of 
which, in a rich field, we shall perceive two oval hazy 
masses in lateral contact, the nebula in question. 
Like other objects of the same nature, this has been 
seen, or at any rate, drawn, in very dissimilar ways; it 
seems in fact almost inseparable from the character of 
nebulous light that its limits and gradations should be 
differently appreciated by different observers ; and in this 
instance the additions resulting from larger apertures 
have almost obliterated the original idea ; yet without 
suspicion of actual change. Minute twinklings are easily 
seen in the haze; and the Earl of Rosse finds a much 
greater abundance of stars than in the surrounding sky ; 
yet he does not resolve it ; and the spectroscope shows it 
as a huge mass of incandescent gas—apparently the little- 
comprehended element nitrogen. 
Quitting now the galaxy for the region on its eastern 
side, we notice, a little above a Aquile, the familiar 
lozenge of De/phinus (a curious instance of configuration) 
the following or left-hand component of which, y, is a 
noble pair of 4th and 7th mags. at nearly 12”, and some- 
what differing in colour now, though Sir W. Herschel 
called them both white in 1779. Physical connection is 
inferred from an extremely slow relative movement ; 
more decidedly from a motion through space common to 
both—an unsolved and insoluble mystery. South of y, a 
little to the west is 3 2725, a very pretty little couple, at 
4'"2 ; possibly of binary character. 
A little further south-east we shall find another less 
conspicuous group of small stars, chiefly in the form of a 
trapezoid. This is Eguu/eus. It is given in Diagram 3, 
where a is at the lowest angle. 
Here y, the 4% mag. star nearest Del/fhinus, forms a 
striking combination with one of 6th mag., and has itself 
been doubled by Knott with an II mag. comes at 2"'1. 
And beyond the limit of the trapezoid to the south-west 
we find a very fine triple, «, R.A. 20h. 53m., D.N. 3° 50’, 
the two closest of which are a beautiful pair in slow rota- 
tion, whose distance, less than 1”, renders it an excellent 
test for a moderate aperture. The third star also appears 
to be physically connected with the others. A, readily 
found by sweeping less than 3° north of the last, and a 
little east, is also well worth looking for : 6 and 63 mags. 
at about 2”. 
We shall now cross the border into Pegasus, the leader 
of which, in respect of position, «, is represented in the 
‘same diagram; a bright yellow 23 mag. star with 2 
comites, 9 and 14 mags. Sweeping rather more than 2}° 
north of this, about 14m. west (R.A. 21h. 24m., D.N. 11° 
38’) we shall come upon M 15, anoble globular cluster, of 
similar character to M 13 in Hercules, but of smaller 
size. Sir J. Herschel gives the stars 15 mag. of his scale, 
running up to a central blaze, and more condensed there 
than according to the idea of equal distribution. It is not 
quite circular, and surrounded with outlying streams. 
Buffham, with a g-inch “ With” mirror, has detected a 
dark patch near the centre, and two faint rifts like those 
in M 13, traces of one of which I think I once perceived. 
This fine object deserves a long and steady gaze. 
About 1° south of the cluster, a little west, we shall 
readily find a beautiful pair, perhaps slow binary, = 2799, 
both 6°6 mag. of Struve’s scale, 1/4 distant. 
Ranging east and west, at some distance below e Pegasz, 
we shall remark the subject of Diagram 4; part of 
Aguarius. At the east end a very remarkable pair, ¢ 
R.A. 22h. 23m., D.S. 0° 38’, will be found in the interior 
of an easily-recognised triangle of stars, not much dif- 
fering in brightness. The magnitudes are given 4 and 
43; the distance 3/"6; the binary character is certain, 
and the period last assigned 1625 years. This is an 
excellent object for a small telescope, and will lead to 
many wondering thoughts as to the possible state of 
existence there. A much larger aperture will be required 
to secure Burnham’s little pair, 8 and Io or II mag, at 
1”°5, 11’ south of ¢ 
To find our next object, M 2, R.A. 21h. 27m., D.S. 
1° 22’, by sweeping, we must note its configuration in the 
diagram with a and 8, two stars conspicuous for insulation 
in a dull region. It will repay the search, being, not 
indeed a brilliant, but a very interesting ball of several 
thousand very minute stars, 15 mag. of Sir J. Herschel, 
“a most superb cluster” in his reflector, “like a heap of 
fine sand,’”’ blazing in centre: D’Arrest sees it of irregu- 
lar form. What an object, could we reach its neighbour- 
hood ! 
But perhaps more surprising, though in quite a different 
way, is the next, HI iv. 1—that is, No. 1 in Sir W. 
Herschel’s fourth class—a noble specimen of what, from 
their equable light and defined edges, the illustrious 
discoverer termed Planetary Nebule. It lies in R.A. 
20h. 58m., D.S. 11° 50’, and, to find it, we may carry a 
line through a and 8 nearly as far again, bending a little 
downwards: this will point out v, a 5th mag. star, a little 
west of which we shall catch our object. It is tolerably 
bright, slightly elliptical, and of a pale blue tint. Lassell 
has seen a luminous well-defined ring in its interior ; 
Buffham, with g-inch mirror, an opening. The Earl of 
Rosse, besides many faint projections, finds a narrow ray 
on either side, making the whole a singular resemblance 
to Saturn with a very thin presentation of the ring. Yet 
here too is gas! and as it seems, nothing but gas! But 
whence? how? wherefore ? 
And now we pass to the left over a long and rather dull 
region from the triangle in Agwarius to the chief star of 
Pisces, at the extremity of the constellation, about 20° 
under the well-known three stars that mark the head of 
Aries. a Pisctum with the head of Cefus east of it are 
shown in Diagram 5. It is a fine pair, 5 and 6 mags. 
at 3’"2, the tints of which, as well as the mags., have been 
described with greater discordance than can be easily 
explained. a Ce#i, the next conspicuous star to the east, is 
a very beautiful specimen of a large orange star, with a 
blue companion at a little distance, the colour of which 
may possibly be due to contrast, or heightened by it: 
this might be ascertained by hiding the great leader 
behind the edge of the field. There is a pretty little pair 
near them. The next star to the right, y, is a striking 
double, 2”°6 apart, 3 and 7 mags., yellow and blue 
(greenish, ruddy, or tawny to some eyes). Above and to 
the right of this is », 44 mag., attended by a very minute 
companion, a glimpse star to Smyth, but much easier of 
late. Below », alittle to the right, is ,a line through 
which from a will point out a very remarkable variable, o, 
. | 
[Vov. 10, 1881 
