Andromeda is very favorable for observation in September, low in the
eastern sky.

Note the characteristic "Y" shaped asterism known as Gloria Frederika
or Frederik's Glory. It lies about at the apex of a nearly isosceles
triangle of which a line connecting Alpheratz and [b] Pegasi is the
base. A line drawn from [d] to [a] Cassiopeiae and prolonged a little
over twice its length points it out.

[Illustration: ANDROMEDA]

PERSEUS (per'-s[=u]s)--THE CHAMPION. (Face Northeast.)

LOCATION.--[a] Persei lies on a line drawn from [b] to [g] Andromedae,
and is about 9[deg] from the latter. The most striking feature in Perseus
is the so-called "segment of Perseus," a curve of stars beginning
about 12[deg] below Cassiopeia, and curving toward Ursa Major. Note the
famous variable Algol the Demon star. It represents the Medusa's head
which Perseus holds in his hand. It varies from the second to the
fourth magnitude in about three and one-half hours, and back again in
the same time, after which it remains steadily brilliant for two and
three-quarters days, when the same change recurs. Algenib and Algol
form with [g] Andromedae, a right-angled triangle.

Note a dull red star near Algol, and a pretty pair just above Algenib.

An opera-glass reveals much that is worthy of observation in this
region of the sky. It has been said of the clusters between Cassiopeia
and Perseus that they form the most striking sidereal spectacle in the
northern heavens. They are visible to the naked eye. Algenib never
sets in the latitude of New York, just touching the horizon at its
lower culmination. It is estimated that Algol is a little over a
million miles in diameter, [[^e]] has three faint stars on one side
nearly in a line, and one on the other--a miniature representation of
Jupiter and his satellites.

Algol, when on the meridian of New York City, is only one tenth of a
degree from the zenith point. This remarkable variable has a dark
companion star revolving near it obscuring its light in part from us
at stated intervals. By means of the spectroscope the speed diameter
and mass of this invisible star has been reckoned.

[Illustration: PERSEUS]

PISCES (pis'[=e]z)--THE FISHES. (Face Southeast.)

LOCATION.--This constellation is represented by two fishes each with a
ribbon tied to its tail. One, the Northern Fish, lies just below [b]
Andromedae,--the other, represented by the circlet, is just below
Pegasus. The ribbons,