As recent events in Switzerland have called the attention of the world to these startling phenomena, perhaps a short summary of what is known of them may be of some service to the readers of the Geological Magazine. In the text-books in use in this country they generally receive little more consideration than the comparatively small scale, on which ‘landslips’ occur in England, would seem to claim for them; and these for the most part occur on the sea-coast. Examples familiar to most of us are such as those of the Isle of Wight, where the Upper Cretaceous strata are known from time to time to slide over the Gault, which is locally known as the “blue slipper,” and that between Seaton and Lyme Regis. On the west coast of South America, in Ecuador, they have been known to occur on a much more gigantic scale in recent years. The tertiary strata of the district of more than 400 feet in thickness consist of sandstones interbedded with clays, and dip towards the coast. The erosive action of the sea eating away the base of the cliffs, and the clays getting softened by water, an enormous portion of the upper strata descended into the sea during the years 1870 and 1871. The landslip of Naina Tal is also fresh in the recollection of most of us. It is however in connexion with the Alps that I propose here to treat of phenomena of this class. The worn-down stumps of ancient mountain-systems which these islands furnish give us only a faint idea of the importance of Bergstürze in relation to the physiography of the Alps, which are of comparatively recent elevation.