Moses in the blessing of Joseph seems to imply that the moon is the source of vegetation to some things. "The precious things put forth by the moon," can hardly bear any other meaning. (Deut. xxxiii. 14.) The margin makes the word "moons," and this indeed may mean the months, each yielding fruit in its appointed season.

*

The blessing of the moon to the earth is very great. "It rules the night;" and in those countries where the sun is so long absent, its presence must be invaluable. Its effects on the earth are very great: this is shown especially in its power over the waters, which, by an inconceivable agency, it draws up immediately under its disk, making that part rise many feet above its usual surface. This action of the moon on the waters, is what is called "THE TIDES," the benefit of which to man cannot be told; for by it the waters are kept continually agitated, and thus are preserved pure; and, in a commercial point of view, watch the Thames, or the Mersey, the Clyde, or the Shannon, or any of the great rivers, on which commerce sends its thousands of ships, and you will at once see the importance of the ebb and flow of the waters. See the anxiety with which mariners of all nations await the "ebb tide" to carry their vessels out of port, and the "flood" to carry them in; and every sailor, and many a landsman too, knows the sprightliness of that sound," THE FLOOD'S MADE," the anchor is

As the waters near the moon are most drawn up, so the waters opposite must be least drawn up; and thus the tide is flood at the same time on both extremes of the globe.

soon up, and THE WHOLE BODY OF THE OCEAN becomes the sailor's friend, to carry him to the port-or the haven where he would be. (Ps. cvii. 30.) But not only does the sailor benefit by the moon in this particular, but many of his most valuable calculations are derived from the same source, especially the lunar observations. Astronomers have divided the circle of the earth into 360 parts, or degrees; and, as once in twenty-four hours the globe performs its daily journey, 360 divided by twenty-four will give the number of degrees that occupy one hour of that journey, i. e. 15. In the time of Charles II., that there might be one general principle of calculation through the empire, the Observatory at Greenwich was made,—as an artificial meridian to the 360 degrees, all to the right of it, until it reached 180 degrees, being in longitude east, and all to the left of it, to 180 degrees, west; so that every fifteen degrees I am east of Greenwich I see the sun an hour earlier, and every fifteen degrees west an hour later.* This is the use of the chronometer, it always telis the time of Greenwich (its owner setting it to a moment when he leaves port;) consequently, if I know the time where I am, (and this the sun will always tell me,) then the difference between the chronometer and my time is my difference of longitude in hours, and one hour being equal to fifteen

Some years since the government held out a reward of 10,000l., and again of 20,000l., to any one discovering a means by which the longitude might be determined, and when Mr. Harrison brought the chronometer to its present state of perfection, the sum was awarded him, as having attained, as far as possible, the desired end. (See Frontispiece.)

degrees, the calculation is soon made. But the watch or chronometer may be wrong, (and it does not do to place implicit confidence in ONE of them; if there are two, and they agree, then, in general, it is safe,) but the lunar observations are invaluable, as a check on the chronometer and common reckoning. The Nautical Almanack gives certain tables which tell the distances between the sun and moon, or the moon and some particular fixed star, at a given time at Greenwichthe distances also observed on board the ship, and the time ascertained,—the difference of time is the difference of longitude. Once on coming from the Chesapeak to Bermuda, a distance only of 600 miles, our common reckoning was out 100 miles, but the lunar observations were correct within two or three leagues; this, however, was thirty years since, and the chronometer was then hardly known; the fact was, we were some days in that extraordinary current called the gulf stream, and then all calculations are baffled that are not made on the heavenly bodies. But not only to the mariner, but especially to the farmer, is the moon invaluable. And here I must tell you something of the HARVEST MOON.

The moon rises later every day, but the time varies at different seasons of the year; sometimes there being an hour's interval, sometimes only a quarter, and at the autumnal equinox even less. At that period, the moon is in that part of her orbit where the time of her rising on successive evenings alters the least; in fact, for some days its * See Appendix.

variation is only a few minutes; it lingers on the earth, as if in sympathy with the harvest man, so that the sheaves may be gathered in. How gracious is this provision, for not only does the Lord "crown the year with his goodness," but by this merciful appointment, prolongs the day. Who can reflect on this and not see the most marked and most merciful design in all the appointments of God! (Ps. lxv. 1-11.)

The moon, like the earth on which it attends, is an opaque body, and derives all its light from the sun. Its diameter is about 2,000 miles, that is, one-fourth of that of the earth, and so its magnitude is only 1-64th of it. Its distance from us is about 240,000 miles, that is, ten times the circumference of the earth; so that a traveller who has gone ten times round the world, has travelled a journey equal to the moon's distance: this calculation seems to bring that planet very near to us; and two hundred days' journey, at fifty miles an hour, would just equal the distance, i. e. 240,000 miles.

THE MOON'S PHASES.

The moon never presents the same appearance to us on two successive evenings; for as it is ever changing its relative position with the sun and the earth, so its PHASES* or appearances vary. We watched the new moon the other evening, the sun had sunk in the

From the Greek word "to see."

western sky; after a little while we discovered its beautiful silver crescent, which seemed to be looking for the sun, as it was the part of its disk near the sun, that was illuminated; the next night the crescent was enlarged, it had caught more of the sun's rays; and in five nights more (for it was on the second day of its age we first saw it,) it was half illumined; and on the fourteenth night it faced the sun, AND THE WHOLE ORB WAS BRIGHT. But you may say, my dear children, if the sun had sunk, and the earth was between it and the moon, would not the earth eclipse the light of the sun, and shut it out from the moon? At times this would be the case; and your question, therefore, leads me to say to you a little about the principle of eclipses.

ECLIPSES.

When the earth is in a direct line between the sun and the moon, (as the latter derives all its light from the sun) it becomes eclipsed; if the earth passes immediately over the centre of the sun, the eclipse is total; if not, its shadow only partially obscures the moon. The same

is equally true of the eclipses of the sun; if the moon, which is an opaque body, passes between the earth and the sun, at a time when the orb of the moon equals that of the sun, if its centre passes over the sun's centre, the eclipse is total, and the stars are seen; but if the orb of the moon is less than that of the sun, and it passes over the centre, then the eclipse is annular, and for a few minutes the sun is seen as a beautiful golden ring in the heavens; but if the moon's