of matter no less than eight thousand miles in thickness. What may be doing there in the centre, four thousand miles beneath our feet, He only knows, whose eye penetrates all substances, and to whom the "darkness is as the light." If fiery oceans there roll, and boiling surges burst, He sees and can curb them, who of old calmed the watery billows, and bade the sea "be still." There, indeed, we know, are tremendous forces working, utterly beyond man's control or understanding. We know them only in their effects. When the great earth quakes and gapes, engulfing whole cities with their people,—when the volcano pours forth its fiery flood, deluging and destroying vast tracts, and burying towns beneath its burning waves, then does man feel his weakness, and confesses that there are powers which only a Hand, infinitely stronger than his own, can master and control.
Yet Geology, though it cannot indeed penetrate to the earth's very foundations, has, nevertheless, from the depths to which it has reached, brought up vast treasures of information. It shews us that the earth's crust, on which we walk and dwell, is constructed on a regular plan; that the great rocks, which are the ribs of its frame, are laid in a certain order, and that an unvarying one. The hand of the Master-Mason is seen to have been, here at work,—silently and steadily, through age after age, preparing this globe for the habitation of man. Geology, too, combined with Mineralogy, tells us what that Hand has been doing both for our comfort and adornment. See the vast stores of fuel, which that good Being, our Preserver equally as our Creator, has been laying up for us before we or our fathers came into existence,—those im-
