. [chi] may be found by noticing that there is a
cluster of small stars in the middle of the triangle formed by the stars
[gamma], [delta], and [beta] Cygni (see Map 4, Frontispiece), and that
[chi] is the nearest star _of the cluster_ to [beta]. The star [phi]
Cygni, which is just above and very close to [beta] (Albireo), does not
belong to the cluster. [chi] is about half as far again from [phi] as
[phi] from Albireo. But as [chi] descends to the 11th magnitude at its
minimum the observer must not always expect to find it very easily. It
has been known to be invisible at the epoch when it should have been
most conspicuous. The period of this variable is 406 days.

The star 61 Cygni is an interesting one. So far as observation has yet
extended, it would seem to be the nearest to us of all stars visible in
the northern hemisphere. It is a fine double, the components nearly
equal (5-1/2 and 6), both yellow, and nearly 19" apart. The period of
this binary appears to be about 540 years. To find 61 Cygni note that
[epsilon] and [delta] Cygni form the diameter of a semicircle divided
into two quadrants by [alpha] Cygni (Arided). On this semicircle, on
either side of [alpha], lie the stars [nu] and [alpha] Cygni, [nu]
towards [epsilon]. Now a line from [alpha] to [nu] produced passes very
near to 61 Cygni at a distance from [nu] somewhat greater than half the
distance of [nu] from [alpha].

The star [mu] Cygni lies in a corner of the constellation, rather
farther from [zeta] than [zeta] from [epsilon] Cygni. A line from
[epsilon] to [zeta] produced meets [kappa] Pegasi, a fourth-magnitude
star; and [mu] Cygni, a fifth-magnitude star, lies close above [kappa]
Pegasi. The distance between the components is about 5-1/2", their
magnitudes 5 and 6, their colours white and pale blue.

The star [psi] Cygni may next be looked for, but for this a good map of
Cygnus will be wanted, as [psi] is not pointed to by any well-marked
stars. A line from [alpha], parallel to the line joining [gamma] and
[delta], and about one-third longer than that line, would about mark the
position of [psi] Cygni. The distance between the components of this
double is about 3-1/2", their magnitudes 5-1/2 and 8, their colours
white and lilac.

Lastly, the observer may turn to the stars [gamma]_{1} and [gamma]_{2}
Draconis towards the north-west about 40 deg. above the horizon (they are
included in the second map of Plate 2). They form a wide double, having