Every reader is aware that in the upper regions of the atmosphere the moisture which is precipitated on the mountain-top assumes the form of snow, while down at the mountain’s base it is rain. In descending a mountain nothing is more common than to pass from one condition to the other—first a storm of dry snow, then moist snow, then water. In Greenland the snow falls dry. The mountains are lofty, and it never rains upon them at all. A fresh layer of snow is laid on every year. Should this continue uninterruptedly, of course the mountains would rise to an indefinite extent. Enormous quantities break loose and roll down the mountain-sides in avalanches; but this is but a small amount in comparison with the deposit. The glaciers are the means of drainage of these great snow-fields. These snow-fields are turned to ice by a very simple process, and the ice flows to the sea. The surface snow on the mountain is white, dry, and light. Deeper down, it is hard; still deeper, it is clear transparent ice. The clear ice which forms such grand and beautiful arches of blue and green in the glaciers as seen along the Greenland coast, was once powdery snow upon the loftiest mountains, probably in the very interior of the continent. The transformation is an interesting process, and the movement of the ice itself from the mountain to the sea is one of the strange mysteries of nature. With respect to the former, Professor Tyndall has stated the case so clearly that I can not refrain from quoting the following passage from his excellent work entitled “The Glaciers of the Alps:”