Page:History of a Six Weeks Tour.djvu/168

 crystal, covered with a net-work of frosted silver. These glaciers flow perpetually into the valley, ravaging in their slow but irresistible progress the pastures and the forests which surround them, performing a work of desolation in ages, which a river of lava might accomplish in an hour, but far more irretrievably; for where the ice has once descended, the hardiest plant refuses to grow; if even, as in some extraordinary instances, it should recede after its progress has once commenced. The glaciers perpetually move onward, at the rate of a foot each day, with a motion that commences at the spot where, on the boundaries of perpetual congelation, they are produced by the freezing