ss we assume what would seem an
unreasonable remoteness for the Hercules cluster, its component stars
must be much smaller bodies than the sun; yet even that fact does not
diminish the wonder of their swarming. Here the imagination must bear
science on its wings, else science can make no progress whatever. It is
an easy step from Hercules to Draco. In the conspicuous diamond-shaped
figure that serves as a guide-board to the head of the latter, the
southernmost star belongs not to Draco but to Hercules. The brightest
star in this figure is gamma, of magnitude two and a half, with an
eleventh-magnitude companion, distant 125", p. 116 deg.. Two stars of
magnitude five compose nu, their distance apart being 62", p. 312 deg.. A
more interesting double is , magnitudes five and five, distance 2.4", p.
158 deg.. Both stars are white, and they present a pretty appearance when
the air is steady. They form a binary system of unknown period. Sigma
2078 (also called 17 Draconis) is a triple, magnitudes six, six and a
half, and six, distances 3.8", p. 116 deg., and 90", p. 195 deg.. Sigma 1984 is
an easy double, magnitudes six and a half and eight and a half, distance
6.4", p. 276 deg.. The star eta is a very difficult double for even our
largest aperture, on account of the faintness of one of its components.
The magnitudes are two and a half and ten, distance 4.7", p. 140 deg.. Its
near neighbor, Sigma 2054, may be a binary. Its magnitudes are six and
seven, distance 1", p. 0 deg.. In Sigma 2323 we have another triple,
magnitudes five, eight and a half, and seven, distances 3.6", p. 360 deg.,
and 90", p. 22 deg., colors white, blue, and reddish. A fine double is
epsilon, magnitudes five and eight, distance 3", p. 5 deg..
The nebula No. 4373 is of a planetary character, and interesting as
occupying the pole of the ecliptic. A few years ago Dr. Holden, with the
Lick telescope, discovered that it is unique in its form. It consists of
a double spiral, drawn out nearly in the line of sight, like the thread
of a screw whose axis lies approximately endwise with respect to the
observer. There is a central star, and another fainter star is involved
in the outer spiral. The form of this object suggests strange ideas as
to its origin. But the details mentioned are far beyond the reach of
our instruments. We shall only see it as a hazy speck. No. 4415 is
another nebula worth glancing at. It is Tuttle's so-called variable
nebula.
[Illustratio
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