James could understand the Cross seeming to perform a circle round the south pole of the heavens, as he had seen the Bear round the north pole, from the rotundity of the earth and its daily motion.
It was quite natural, then, that the lad should be so enthusiastic when he spoke of the constellation to his father in these terms:
“O that pretty Southern Cross! I like it more and more as I get down to the south. I did feel sad to see the old Bear drop gradually, night after night, till it seemed to sink for ever in the northern Atlantic; but I have a new friend here, that keeps rising higher and higher each night, as if to welcome us to our southern home. How it would please many boys in Europe to see the Cross!
But it was seen in Europe formerly.
Another puzzle, dear father. Did it run away from the south pole to have a look at the north one?
It was not a run, but a gradual slide out of its place, and as gradual a slide back into it again.
What a queer trick! Is it on its rambles now, I wonder?
It is always on the move.
Yes; I know it describes a circle in the sky once in twenty-four hours, but that is owing to the world rolling over to get its daily light.
Yet it has another motion; not really its own any more than the other. And this leads it further away from the central point over our south pole, and then brings it to its place again.