an has been commonly
supposed, and that the mere irresolvability of a cluster is no proof of
excessive distance. It is unlikely that the faintest component of the
cluster is farther off than the brightest (a seventh-magnitude star) in
the proportion of more than about 20 to 19, while the ordinary estimate
of star magnitudes, applied by Herschel, gave a proportion of 20 or 30
to 1 at least. I can no more believe that the components of this cluster
are stars greatly varying in distance, but accidentally seen in nearly
the same direction, (or that they form an _enormously long system_
turned by accident directly towards the earth), than I could look on the
association of several thousand persons in the form of a procession as a
fortuitous arrangement.
Next there is the great nebula in Andromeda--known as "the
transcendantly beautiful queen of the nebulae." It will not be difficult
to find this object. The stars [epsilon] and [delta] Cassiopeiae (Map 3,
Frontispiece) point to the star [beta] Andromedae. Almost in a vertical
line above this star are two fourth-magnitude stars [mu] and [gamma],
and close above [nu], a little to the right, is the object we
seek--visible to the naked eye as a faint misty spot. To tell the truth,
the transcendantly beautiful queen of the nebulae is rather a
disappointing object in an ordinary telescope. There is seen a long
oval or lenticular spot of light, very bright near the centre,
especially with low powers. But there is a want of the interest
attaching to the strange figure of the Great Orion nebula. The Andromeda
nebula has been partially resolved by Lord Rosse's great reflector, and
(it is said) more satisfactorily by the great refractor of Harvard
College. In the spectroscope, Mr. Huggins informs us, the spectrum is
peculiar. Continuous from the blue to the orange, the light there
"appears to cease very abruptly;" there is no indication of gaseity.
Lastly, the observer may turn to the pair Mizar and Alcor, the former
the middle star in the Great Bear's tail, the latter 15' off. It seems
quite clear, by the way, that Alcor has increased in brilliancy of late,
since among the Arabians it was considered an evidence of very good
eyesight to detect Alcor, whereas this star may now be easily seen even
in nearly full moonlight. Mizar is a double star, and a fourth star is
seen in the same field of view with the others (see Plate 5). The
distance between Mizar and its companion is 14".4; the
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