Giants' Kettles

Giants' Kettles, the name given in Norway to vertical pot-shaped, smooth-sided hollows excavated in rocks, usually filled up with rounded boulders, water-worn stones, gravel, and other detritus. They are believed to have originated under the great glaciers or continuous mer de glace which formerly covered wide regions of northern Europe (see BOULDER-CLAY, GLACIAL PERIOD, PLEISTOCENE SYSTEM). They have probably been formed by water descending from the surface of the ice through monlins or glacial chimneys—setting stones and boulders in rapid rotation. They are thus comparable to the pot-holes which are so common a feature in the beds of rapid streams, particularly in the neighbourhood of waterfalls, where the stones have a gyratory motion imparted to them by the irregular movements of the water. As they rotate they gradually wear away the rock, and produce more or less steep-sided cavities. Giants' kettles occur in connection with the glacial deposits of many other countries besides Norway; as, for example, in Prussia.