Let us turn once more to the Southern Cross to find the ancient constellations. It is both ancient and modern itself, for its stars were known to the Greeks of Alexandria, but were included in the Centaur. The latter, like all those shown in the accompanying illustration, is of great antiquity, and probably of Babylonian origin. The two stars which we call the Pointers to the Cross are Alpha and Beta of the Centaur, and mark his forefeet. Another conspicuous pair, Delta and Gamma, are on his horse’s body, while his man’s shoulders are marked by many bright stars, and the head is formed by a little group. His arm stretches out through bright Eta to Kappa, which is very close to Beta Lupi. For the Centaur and Lupus form one large and very brilliant group, and were perhaps connected with the little constellation of Ara, the Altar, upon which the Centaur seems to have been imagined as offering the creature which we now know as the Wolf, though its older name was simply the Beast. Aratus, a Greek poet of about 300 b.c., to whom we owe the earliest description extant of the ancient constellations, says of the Centaur:

On the other side of the Cross is another splendid constellation, the Ship Argo, which covers a large space of the sky with many bright stars, among them Canopus, the brightest in the whole heavens except Sirius. For convenience this large constellation has been divided into four—the Keel, the Poop, the Mast, and the Sails.

Sirius is north of Canopus, in the constellation of the Great Dog—Orion’s Dog, as it is often called, for Orion is a hunter with two dogs; but the Little Dog is in the northern hemisphere, and Orion himself has his head in the north and his feet in the south, his famous belt and sword lying just south of the equator. Thus he is visible all over the world, and only at the poles would his feet or his head never rise above the horizon. Beneath his feet is the little Hare, as Aratus says:

Four stars of the Hare (α, β, γ, δ), which form a small square, were called by the Arabs the “Throne of the Giant” (i.e. of Orion); or sometimes “those which quench the thirst of the camel,” in allusion to the river of the Milky Way which flows close by. Orion is mentioned in the books of Job and Isaiah, and also by Hesiod and Homer.

Above the Centaur and the Ship Argo stretches the long straggling constellation of Hydra, the Water-Snake. Its head reaches beyond the equator into the northern hemisphere, but the beautiful red star Alphard is in our hemisphere. This Snake is oddly connected with a Crow and a Cup, which are somehow perched on its back. (I have seen a snake pursued by an Indian crow, which kept pecking at its tail until the snake found refuge in a stream.) Crater, the Cup, has no bright stars; Corvus, the Crow, is an irregular little square which sailors call Spica’s Spanker, a spanker being a sail of this shape, and two stars of the four point to Spica, the bright star of the Virgin.

Virgo, the Virgin, is one of the constellations of the Zodiac, that zone of stars which marks the apparent pathway of sun, moon, and planets in the sky. All the twelve zodiacal constellations can be seen in both hemispheres, but those south of the equator, which are least well seen in northern countries, are of course the best seen in the south. These are the Scales, Scorpion, Archer, Sea-Goat, and Water-carrier, with a very small part of the Fishes, and the part of Virgo which contains her brightest star, Spica, the Ear of Corn held in her hand. The Romans called her the Goddess of Justice, but these constellations were invented long before Rome was a great power, and the ear of corn shows that she was rather a goddess of the fields. They added that the Scales were her balance wherein she weighed the deeds of men, but this constellation was of much later origin than the Virgin: its place was earlier held by the Claws of the Scorpion.[3] In some old books we find a compromise between the two ideas, for a pair of tiny scales is hung on the great claws of Scorpio.

Scorpio is a magnificent constellation as seen in the south. In England it merely creeps along the southern horizon in the pale summer skies, but in southern countries its whole splendid length rises high and shines, from the bright stars in its head and the ruby Antares on its back to the sting in its tail, represented by two stars close together.

Close behind Scorpio is Sagittarius, the Archer, also a brilliant constellation, with his bow strung ready to shoot the Scorpion; he is a centaur, like the figure near the Southern Cross. He is followed by Capricornus, a very strange animal, for it has the head and horns of a goat and the tail of a fish. As a modern writer quaintly says:

Capricorn has very few bright stars. There are two in his goat’s head, of which the brightest, Alpha, is a beautiful naked-eye double, and there are two in his fish’s tail. These three figures—a Scorpion, Centaur-archer, and Capricorn—are carved on old Babylonian boundary-stones belonging to the second millennium b.c.

Following these is Aquarius, the Water-carrier, his shoulder marked by the star β, and his pot by four stars (α, γ, ζ, η), from which fall splashes and streams of faint stars, aptly representing the water which he is pouring out. He is a familiar figure to those who have lived in some countries of the East where water is all carried by hand.

This is a very watery part of the heavens, for the zodiacal pair of Fishes follows the Water-carrier (their only bright star in the northern hemisphere), and there is also a solitary Fish, Piscis Australis, swimming in the water poured out; while a little further east is the great Sea-Monster, which belongs to the northern group of Perseus and Andromeda and her parents Cepheus and Cassiopeia. Only the head of Cetus, the Sea-Monster, is in the northern hemisphere, but that contains its brightest star. Between the dim Sea-Monster and the bright Orion flows the winding River Eridanus: it rises near Orion’s foot, and now ends very far south in the bright star Achernar; but this star was not visible to Ptolemy when he drew up his star-catalogue in Alexandria, and the original Achernar, or Last-of-the-River, seems to have been what we now call Theta Eridani, which was much brighter some centuries ago than it is now. Al-Sufi, an Arab writer of the tenth century a.d., calls it a star of first magnitude.

To complete our survey of the constellations south of the equator we must add the tip of the Eagle’s wing, the legs of the Unicorn, and part of Ophiuchus with the Serpent he is strangling as he treads the Scorpion under foot (a gallant hero, to contend with both these enemies at once).

It is worth noting that just as the three stars of Orion’s belt mark the celestial equator in one part of the sky, so the three bright stars of the Eagle mark it in the opposite part (Altair, with β and γ on either side); but they are just north of it, and Orion’s belt is just south. As it is often interesting to know where the ecliptic lies, we may point out that the following southern stars lie near it: Spica, α Librae, Antares, α and β Capricorni (and in the north the Pleiades, Aldebaran, Regulus). It is also convenient to remember the positions of a few constellations as a guide to right ascension. Thus, Achernar is in the Ist hour, Canopus and Sirius are in the VIth, the Cross and Corvus in the XIIth, and the Bow of Sagittarius is in the XVIIIth.[4]

There are more bright stars in the southern hemisphere than in the north, for a count of all those above fourth magnitude shows that there are 228 south of the equator against only 164 north. But whereas the stars in the north are fairly evenly distributed, there is a more strongly marked tendency in the south to congregate on the Milky Way, so that, while the tract through Argo and the Cross to Scorpio and Sagittarius is extraordinarily rich, the part between Orion and Fomalhaut is comparatively dark and bare, and the regions round the south pole and north of Argo are also very barren of bright stars. Some regions, however, which look dull to the eye abound in marvels for the telescope and camera.

The brilliance and the complex structure of the Milky Way is undoubtedly what most strikes the northerner travelling south. In England we have a glimpse of it in Cygnus and Aquila, where this rich and bright part begins; but there is nothing to equal the brightness or the mingling of dark and light which we see in Argo and near the Cross, in Scorpio and in Sagittarius. When this part is about to rise, there is often a glow on the horizon as if it were dawn.