[135] when the fiery principle which is contained beneath, in the earth, is thrust upwards by the natural power of fire, it proceeds to its own appropriate place; and if it meets with any respite or [38] relaxation, though ever so slight, it draws up with it a large portion of the earthy substance, as much as it can; and when it has emerged from the earth it proceeds more slowly; but the earthy substance being compelled to follow it for a long time, being at last raised to an immense height, is contracted at the top, and at last comes to end on a sharp point imitating the general appearance of the flame of fire;