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We must not, however, forget the many important respectsin which the Moon is an object of interest to those who arenot only unable to photograph her image, but who havenot even a telescope to aid their view. Such observers maycarefully watch the very considerable changes in the apparentsize of her disc, by which, as explained in our previous lecture,it is increased from time to time by as much as one-thirdpart of its least value ;—times of which Othello says :—
“ It is the very error of the Moon ;
She comes more nearer earth than she was wont.”
They may also notice that at such times the tides are cor-respondingly intensified, and that, if spring tides also occurwhen the Moon ’s distance is unusually small, and certainconditions of wind and weather act conjointly, the inundationsof the Thames and of other tidal rivers may prove to be veryserious.
It is also interesting for the unscientific observer to notehow conveniently the Moon ’s path in the heavens is arranged,so that we enjoy a far greater amount of moonlight in winterthan in summer. We do not mean, that, the nights beinglonger in winter, we notice the Moon ’s light more, in the absenceof that of the Sun ; but that the Moon is in mid-winter abovethe horizon for a longer time on those nights during each monthwhen its phase affords a greater amount of light, and for thelongest time of all when it is full, or nearly so; while in mid-summer it is a shorter time above the horizon when full, ornearly so, than in any other part of the lunar month.
In fact, the increase in the hours of moonlight thus obtainedin winter bears a close relation to that of the hours of sunlightin summer. This arises from the fact that the Moon ’s path, asseen amongst the stars, differs, month by month, very littlefrom the great circle of the heavens called the ecliptic, whichis the Sun ’s apparent annual path. And the Moon , when full,being very nearly in a straight line with the Sun and the Earth ,but upon the opposite side of the latter, it follows that a fullMoon will at midnight be always seen nearly in the sameposition in the sky as that in which the Sun was seen at noonsix months previously. The path of the Full Moon across the