know it is the reflected rays of the sun which makes the crescent visible, but how is it that we are thus able to see the rest of the moon upon which the sun is not shining? It is by what is termed "earth-shine," or by reflection of those rays which in our quality of moon we send across to her. The "earth-shine" on the moon is pale and shadowy, but we must recollect that the rays which bring it to us have travelled over many a weary mile. They sprang originally from the fountain of the sun, and had first to speed across some 92 millions of miles before they reached our shores. They were then the young and joyous rays that dazzled our eyes by their brightness. Earth having caught them up, next sent them, softened into mild moonlight, across, the 240,000 miles of space that separates us from our satellite. And lastly, after having brightened up Luna's rugged surface, these wasted remnants of light were cast back once more across the wide sea of ether to the Earth, carrying with them to our eyes the dim image of the moon they had left behind.

Some may be inclined to ask,-How happens it that this earth-shine is not seen at other phases of the moon? It arises from the circumstance that the crescent moon always coincides with the period when our fully illumined disk is turned towards it. We are then at the "full." Our lamp-power, therefore, is at its highest, and is strong enough to produce the earth-shine. But when the moon is about half full, not only is our lamp-power diminished. from our "phase" in relation to the moon having been changed, but the more extensive illumination of the moon herself by the direct rays of the sun obscures and, as it were, "puts out" the more feeble earth-shine that was previously visible.

From the comparative nearness of the moon, and the perfection gradually imparted to optical instruments,

many have been bold enough to anticipate that we shall one day see in it the familiar objects of every day life, or even the Lunarians themselves, if any exist. This rather unreasonable expectation has been from time to time encouraged by fallacious announcements. Thus, on one occasion, it was given out that a town had been plainly descried in the moon; on another, that a fortification, with roads and canals, was equally discernible. But these supposed discoveries have never received subsequent confirmation. On the contrary, Mädler, of Berlin, has pointed out that it is in the highest degree improbable we shall ever be able to detect objects so small as the human figure. The extreme distance, he remarks, at which a man is visible to the unassisted eye, is a German league. Now, to bring an object in the moon to that apparent distance would require a magnifying power of 51,000, a power which, with all our modern skill in instrument-making, we can never expect to attain.

Scripture as well as experience and common sense tell us that the moon was made "to rule the night," but some have objected to the obvious meaning of the expression, if not to the perfection of the work itself, on the ground that the "lamp" is only occasionally lighted up. The observations of Laplace certainly sanctioned the opinion that the moon might possibly have been placed in the heavens in such a position as to be always "full" to us; but this advantage could only have been purchased at the cost of the loss of light arising from increased distance. As things are actually regulated, moonlight brightens our earth on most nights of the year, and we are never long without practically experiencing the advantage of the light placed by Our Father in the heavens for our use. In arctic regions the moon and the stars alone temper the darkness of the long winter's night, and all who have read the story

of polar voyages will recollect the thankfulness with which the moonlight is welcomed. The Arab of the desert steers on emergency by the light and position of the moon. Over the pathless seas the moon is the navigator's friend and counsellor, and places within his reach a sure means for measuring the longitude, and fixing the spot where the ship may be. When we think of the fleets of noble vessels with their wealth of merchandise, and the thousands of lives whose safety is dependent on its teachings, we may form some estimate of the value of this blessing. "Without the moon's aid," an astronomer observes, "our ships, instead of fearlessly traversing the ocean from pole to pole, would probably even now be incapable of performing long voyages, and would content themselves with exchanging commodities and intelligence between well-known and neighbouring shores."

Of old the moon played a more important part than she now does in the notation of time; but, among many Eastern peoples, it still indicates the seasons, while its different phases serve as an almanack to mark particular days. Among the Jews the new moon was associated with certain religious ceremonies, and men. were stationed on the hill-tops to give the earliest notice of its approach. Some Orientals are also accustomed to indicate the seasonal stages of vegetable life by the epithets they apply to the moon; thus there is the ricemoon, the wild-strawberry moon, the leaf-falling moon, and there is likewise an ice-moon. We have, at least, our glorious harvest-moon. Nor is our satellite unrecognised in our Church festivals; for Easter is always celebrated on the Sunday following the first full moon which happens on or after the 21st March, or vernal equinox.

The Heavens declare the glory of God; and the firmament sheweth His handiwork.-Ps. xix.

THE STARS OF HEAVEN.

O ye stars of Heaven, bless ye the Lord: praise Him, and magnify Him for ever.

E who turns his thoughts star-wards will speedily find his power of distinct conception strained

to its utmost effort; for as the distances, magnitudes, and movements familiar to us upon earth are dwarfed by those of the Solar system, so do the latter in their turn shrink into insignificance when compared to the distances, magnitudes, and movements of the Stellar Universe. Miles now become useless, and no longer speak to us with their old intelligible meaning; while the other familiar aids that helped us on in the comprehension of Solar measurements are scarcely more serviceable. The locomotive with its 30 miles an hour, the cannon-ball with its flight of 500 miles an hour, are all too slow to mete out distances such as are now to occupy us. Nothing but light itself, cleaving through space with a velocity of 192,000 miles a second-or, according to Foucault's latest estimate, 186,000 miles a second-can supply us with a standard capable of representing the remoteness of the more distant stars.

In the immensity of the existences revealed by

astronomy we miss those homely illustrations of providential design so often impressed upon us in our daily experience by the familiar objects around us. But, on the other hand, we behold in their mightiest development the laws governing that Universe of worlds which peoples the realms of space, and among which our spot of earth occupies so humble a position. In presence of this grand view the physical details of our little globe seem almost too petty to be remembered. The Omnipotence of God confronts us with all the vividness which our imperfect understanding can conceive, and we bow our heads in humble adoration.

By the Word of the Lord were the Heavens made, and all the hosts of them by the breath of His mouth.-Ps. xxxiii.

The "Hosts of Heaven" are truly called innumerable; and, as we glance upwards on a clear, starry night, the twinkling points that meet our gaze in all directions seem to defy enumeration. Yet, strange though it may appear, the sum of all the stars that can be distinguished by the naked eye in both hemispheres under the most favourable circumstances does not exceed 6000, and of these considerably less than half belong to our northern division. But, when the telescope is turned towards the sky, stars come forth in myriads from the dark depths of the firmament; and, as each additional light-grasping power is given to the instrument, a new region of the heavens is joined on to those already explored, while every stratum of space thus added to vision is found to be studded with stars in an ever increasing ratio. It is difficult to estimate the number which may thus be brought into view, but astronomers compute it to be not less than 100 millions. To a superficial observer the stars seem scattered about as if by chance, but a more careful inspection reveals that