THE SURFACE OF THE MOON.

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ties of great extent and depth; the bright circular spots of this place areconsidered to he insulated mountains, or peaks, highly illuminated. Kepler issituated on the eastern, or left border of the moon, at the distance of about one-fourth of her diameter from the edge.

Scene No. LXXIV.— The Moon ’s Surface: Cleomedes .

This is one of the most remarkable and distinctly marked spots of themoon; it is the dark elliptical spot , always visible to the naked eye, on thewestern border of the disc, or the right border of the moon, as we see it.Through the telescope this vast hollow appears raised in its middle portion,with an immense ridge of rocks stretching across its width, from its upper, ornorthern margin, to its lower. The borders of this hollow are, on all sides,continuous ridges of rocks.

Scene No. LXXV.— The Moon ’s Surface : Fracastorius .

This spot is situated on the south-western part of the moon’s disc, or on theright side, about one-fourth of her diameter from the lower edge. Its upperportion is a vast hollow; and on its lower, or southern border, are two remark-able cavities of greater depth, and bordered by an annular ridge of high rocks,from which radiates an extensive straight ridge of heights, brightly illuminated ;smaller mountain peaks are interspersed ; and on the right, or western side, aremarkable elevation is seen, having a high annular ridge surrounding it, andan insulated peak in its centre.

Scene No. LXXVI.— The Moon ’s Surface : Tycho.

This is the remarkable spot, on the lower part of the moon’s disc, which isalways distinctly visible to the naked eye, and which seems the centre of thosebright radiating lines of spots, which richly cover the south-western, or right-handlower portion of the moon. Caverns, or hollows, occur most frequently in thisquarter ; and it is from this circumstance that it is the most brilliant part of themoon’s surface. The mountainous ridges, which encircle the cavities, exhibit thegreatest quantity of light; and, from their lying in all directions, with an uniformdistribution, and yet radiating from the central spot, they seem passages to thevast cavity in which the bright spot is situated. This cavity is estimated to befifty miles broad, and nearly three miles in depth.

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