farther afield. For instance, we may begin with our closest neighbour of all, the Moon; and with our brother and sister worlds, the planets; and with the great head and centre of our system, the Sun; afterwards passing on to the stars.

But even from the first we cannot ignore the stars. Night by night, unless hidden by clouds, they shine forth; and from childhood those tiny glimmers are a part of our lives.

With them the earliest stage should be just to grow used to their ordinary look, as seen from our Earth; to learn something of the various groups or "constellations;" to become acquainted with the shapes and names of such constellations, and their places in the heavens; also to understand a little about their seeming nightly and yearly movements, due to our own daily and yearly revolvings. What they really are, and how far they truly and actually move, must come later.

Earth's daily whirl on her own axis has been explained as making all the sky seem to travel round us by day and by night. And her yearly journey round the Sun also causes a slow shifting-apparent, not real—of the various constellations through summer and winter.

Certain constellations, far north, such as the Great Bear and the Little Bear, are always visible to us in Great Britain and in the northern parts of Europe and North America. Certain constellations, such as the Southern Cross, are never visible to us in those regions. But other constellations, not so far north and not so far south, are sometimes to be seen, and sometimes not. Many stars, high up in the southern sky-for instance,

those in the constellation of Orion-visible to us in winter nights, are hidden in summer nights.

We can at any time see only those groups which lie in a direction away from the Sun; not those which lie on the same side of the heavens with the Sun. Those stars, if seen at all, would have to be seen by daylight; that is, at the same time as the Sun. And this, under ordinary conditions, is out of the question, because they are veiled from our eyes by the glare of sunlight.

So it is not till the Earth, in her twelve-months' voyage, gets round to the other side of the Sun, and sees him against the opposite heavens, that the stars which were hidden months before become visible. While, from the same cause, many stars which have been visible take their turn to disappear.

One fact should from the first be absolutely clear. This is that the stars are always there. They do not come and go. They are always overhead, high in the heavens, round the whole Earth, whether we do or do not see them.

I do not mean that the same stars are always over one particular part of the world; but that some stars are there always, which of them depending on which part of the heavens our part of the Earth happens to be under at any particular hour. The whole vast company of stars, each in its own constellation, to which it has belonged through thousands if not millions of years, is always in the skies.

If you had a good telescope, with a friend able to use it, you might get a glimpse of certain stars, even in the brightest noonday.

Picture to yourself a small toy balloon floating in the air of a vast hall, with walls and ceiling and floor, pictures and furniture, surrounding it above and below and on all sides. So our Earth floats in the measureless expanse of space, with countless stars above and below and on all sides.

Think of a small spider clinging to that little balloon. He would be able to see only part of the hall, whichever part towards which his side of the balloon happened to face. If he were looking at the right wall, he could not see the left, because the balloon between would hide it. And just so we on Earth can, at any particular time, see only that part of the heavens towards which our side of this floating globe is turned.

Longfellow wrote on the subject—

"And as the evening twilight fades away,
The sky is filled with stars, invisible by day."

And Wordsworth

"Look for the stars, you'll say that there are none;
Look up a second time, and one by one

You mark them twinkling out with silvery light,
And wonder how they could elude the sight.'

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The above illustration of balloon and hall is, of course, defective, as such illustrations are bound to be. On Earth we know no true up or "down," down," except in the sense of towards and away from our Earth's centre. This is just as true in Australia as in Britain, even though the feet of our fellow-subjects there do point towards the feet of men walking on British soil here.

Picture once again to yourself the small globe floating in the great hall, about half-way between floor and ceiling. But now think of it as obeying rule, as floating round and round a centre which is occupied by another and much larger ball. Picture also that a slender needle is thrust through the little balloon's centre, one end coming out at its north pole, the other at its south pole. And as it moves that needle is slanting, not upright, and the slant is always in the same direction. The needle does not wobble about, pointing this way and that way. It points always steadily towards the same wall.

So does the axis of our Earth keep always the same slant; and our north pole points always towards one part of the heavens. There lies the celestial north pole, carried straight on from the north pole of our little world.

In this slant of our Earth's axis lies the explanation of our seasons.

For in one part of our yearly journey round the Sun our north pole points towards the Sun, and our south pole is turned away from him. This means the northern summer and the southern winter. Six months later it is the south pole which points towards the Sun, and the north pole which is turned away from him. And though, during that northern winter, we are really nearer to the Sun than in our summer, the trifling difference of three million miles is of little account. The main fact is that we have so much less of actual direct sunshine, and that it comes to us from a Sun far lower down in the sky. Spring and autumn lie between these two extremes, when the Earth is in a half-way position.

II. HOW TO KNOW THE STARS

It is a good plan to cultivate the habit of looking from some particular window at certain stated hours after dusk each evening. Much may be learnt thus.

The brighter stars should first be picked out and carefully watched. It may be noted how they are placed with respect to neighbour-stars not quite so bright: whether they twinkle or shine steadily; whether they keep, night after night, at the same distance from those other stars, or whether they slowly alter their positions; and if they do move, how they move.

This is one of the first questions of interest, because thereby one may distinguish between stars and planets. A star twinkles; a planet generally does not. A star keeps always the same position among other stars; a planet wanders about from one place to another among the stars.

Many years ago a working-man wrote to my father, begging for help in his efforts to learn about the heavenly bodies. In his letter he made this remark: "If I can once get hold of Venus, I will not let her go."

No better plan could be suggested. Try to "get hold" of a planet here, of a star there, and do not let them go, do not lose them, but follow their movements day by day.

Bad weather may interrupt and confuse such attempts, and for a while your new friends may slip out of sight, but they can be found again. They never really take their departure; they only change their positions. The stars only change theirs in appearance, though in more ways than one. The planets change theirs, not