are the stars [zeta] and [beta] Tauri. If with a low power the observer
sweep from [zeta] towards [beta], he will soon find--not far from [zeta]
(at a distance of about one-sixth of the distance separating [beta] from
[zeta]), the celebrated Crab nebula, known as 1 M. This was the first
nebula discovered by Messier, and its discovery led to the formation of
his catalogue of 103 nebulæ. In a small telescope this object appears as
a nebulous light of oval form, no traces being seen of the wisps and
sprays of light presented in Lord Rosse's well known picture of the
nebula.

Here I shall conclude the labours of our first half-hour among the
stars, noticing that the examination of Plate 1 will show what other
constellations besides those here considered are well situated for
observation at this season. It will be remarked that many constellations
well seen in the third half-hour (Chapter IV.) are favourably seen in
the first also, and _vice versâ_. For instance, the constellation Ursa
Major well-placed towards the north-east in the first quarter of the
year, is equally well-placed towards the north-west in the third, and
similarly of the constellation Cassiopeia. The same relation connects
the second and fourth quarters of the year.

[Illustration: PLATE III.]




CHAPTER III.

A HALF-HOUR WITH LYRA, HERCULES, CORVUS, CRATER, ETC.