But some other singular relations are to be noted in connection with the particular epoch I have indicated.
It is tolerably clear that in imagining figures of certain objects in the heavens, the early observers would not be apt to picture these objects in unusual positions. A group of stars may form a figure so closely resembling that of a familiar object that even a wrong position would not prevent the resemblance from being noticed, as for instance the 'Chair,' the 'Plough,' and so forth. But such cases are not numerous; indeed, to say the truth, one must 'make believe a good deal' to see resemblance between the star-groups and most of the constellation-figures, even under the most favourable conditions. When there is no very close resemblance, as is the case with all the large constellations, position must have counted for something in determining the association between a star-group and a known object.
Now the constellations north of the equator assume so many and such various positions that this special consideration does not apply very forcibly to them. But those south of the equator are only seen above the southern horizon, and change little in position during their progress from east to west of the south point. The lower down they are the less they change in position. And the very lowest—such as those were, for instance, which I have been considering in determining the position of the southern pole—are only fully visible when due south. They must, then, in all probability, have stood upright or in their natural position when so placed, for if they were not rightly placed then they only were so when below the horizon and consequently invisible.
Let us, then, inquire what was the position of the southernmost constellations when fully seen above the southern horizon at midnight.
The Centaur stood then as he does now, upright; only—whereas now in Egypt, Chaldæa, India, Persia, and China, only the upper portions of his figure rise above the horizon, he then stood, the noblest save Orion of all the constellations, with his feet (marked by the bright Alpha and Beta still belonging to the constellation, and by the stars of the Southern Cross which have been taken from it) upon the horizon itself. In latitude twenty degrees or so north he may still be seen thus placed when due south.
The Centaur was represented in old times as placing an offering upon the altar, which was pictured, says Manilius, as bearing a fire of incense represented by stars. This to a student of our modern charts seems altogether perplexing. The Centaur carries the wolf on the end of his spear; but instead of placing the wolf (not a very acceptable meat offering, one would suppose) upon the altar, he is directing this animal towards the base of the altar, whose top is downwards, the flames represented there tending (naturally) downwards also. It is quite certain the ancient observers did not imagine anything of this sort. As I have said, Aratus tells us the celestial Centaur was placing an offering upon the altar, which was therefore upright, and Manilius describes the altar as
Ferens thuris, stellis imitantibus, ignem,
so that the fire was where it should be, on the top of an upright altar, where also on the sky itself were stars looking like the smoke from incense fires. Now that was precisely the appearance presented by the stars forming the constellation at the time I have indicated, some 2170 years B.C. Setting the altar upright above the southern horizon (that is, inverting the absurd picture at present given of it) we see it just where it should be placed to receive the Centaur's offering. A most remarkable portion of the Milky Way is then seen to be directly above the altar in such a way as to form a very good imitation of smoke ascending from it. This part of the Milky Way is described by Sir J. Herschel, who studied it carefully during his stay at the Cape of Good Hope, as forming a complicated system of interlaced streaks and masses which covers the tail of Scorpio (extending from the altar which lies immediately south of the Scorpion's Tail). The Milky Way divides, in fact, just above the altar as the constellation was seen 4000 years ago above the southern horizon, one branch being that just described, the other (like another stream of smoke) 'passing,' says Herschel, 'over the stars Iota of the Altar, Theta and Iota of the Scorpion, etc., to Gamma of the Archer, where it suddenly collects into a vivid oval mass, so very rich in stars that a very moderate calculation makes their number exceed 100,000.' Nothing could accord better with the descriptions of Aratus and Manilius.
But there is another constellation which shows in a more marked way than either the Centaur or the Altar that the date when the constellations were invented must have been near that which I have named. Both Ara and Centaurus look now in suitable latitudes (about twenty degrees north) as they looked in higher latitudes (about forty degrees north) 4000 years ago. For, the reeling motion of our earth has changed the place of the celestial pole in such a way as only to depress these constellations southwards without much changing their position; they are nearly upright when due south now as they were 4000 years ago, only lower down. But the great ship Argo has suffered a much more serious displacement. One cannot now see this ship like a ship at any time or from any place on the earth's surface. If we travel south till the whole constellation comes into visibility above the southern horizon at the proper season (January and February for the midnight hours) the keel of the ship is aslant, the stern being high above the waist (the fore part is wanting). If we travel still further south, we can indeed reach places where the course of the ship is so widened, and the changes of position so increased, that she appears along part of her journey on an even keel, but then she is high above the horizon. Now 4000 years ago she stood on the horizon itself at her southern culmination, with level keel and upright mast.
In passing I may note that for my own part I imagine that this great ship represented the Ark, its fore part being originally the portion of the Centaur now forming the horse, so that the Centaur was represented as a man (not as a man-horse) offering a gift on the Altar. Thus in this group of constellations I recognise the Ark, and Noah going up from the Ark towards the altar 'which he builded unto the Lord; and took of every clean beast, and of every clean fowl, and offered burnt offerings on the altar.' I consider further that the constellation-figures of the Ship, the Man with an offering, and the Altar, painted or sculptured in some ancient astrological temple, came at a later time to be understood as picturing a certain series of events, interpreted and expanded by a poetical writer into a complete narrative. Without venturing to insist on so heterodox a notion, I may remark as an odd coincidence that probably such a picture or sculpture would have shown the smoke ascending from the Altar which I have already described, and in this smoke there would be shown the bow of Sagittarius; which, interpreted and expanded in the way I have mentioned, might have accounted for the 'bow set in the clouds, for a token of a covenant.' It is noteworthy that all the remaining constellations forming the southern limit of the old star-domes or charts, were watery ones—the Southern Fish, over which Aquarius is pouring a quite unnecessary stream of water, the Great Sea Monster towards which in turn flow the streams of the River Eridanus. The equator, too, was then occupied along a great part of its length by the great sea serpent Hydra, which reared its head above the equator, very probably indicated then by a water horizon, for nearly all the signs below it were then watery. At any rate, as the length of Hydra then lay horizontally above the Ship, whose masts reached it, we may well believe that this part of the picture of the heavens showed a sea-horizon and a ship, the great sea serpent lying along the horizon. On the back of Hydra is the Raven, which again may be supposed by those who accept the theory mentioned above to have suggested the raven which went forth to and fro from the ark. He is close enough to the rigging of Argo to make an easy journey of it. The dove, however, must not be confounded with the modern constellation Columba, though this is placed (suitably enough) near the Ark. We must suppose the idea of the dove was suggested by a bird pictured in the rigging of the celestial ship. The sequence in which the constellations came above the horizon as the year went round corresponded very satisfactorily with the theory, fanciful though this seem to some. First Aquarius pouring streams of water, the three fishes (Pisces and Piscis australis), and the great sea monster Cetus, showing how the waters prevailed over the highest hills, then the Ark sailing on the waters, a little later the Raven (Corvus), the man descending from the ark and offering a gift on the Altar, and last the Bow set amid the clouds.