The Lake of Paladru (Isère) which has been searched by M. Gustave Vallier, has afforded similar results. Pile-works are thought to exist in some other small lakes in the same district--those of Sainte-Hélène, on the left bank of the Isère, Saint-Martin-de-Belville, and Saint-Marcel, near Moutiers. Pile-works have also been discovered on the site of an ancient lake on the banks of the Saône; and in a totally different district, at the foot of the Pyrenees, as many as five have been pointed out. Everything therefore leads us to believe that if we searched with care the peat-mosses and pools which are very common in a good many of the French departments, we should discover the vestiges of various pre-historic epochs. In order to complete the enumeration of the lacustrine constructions of Europe, we may state that they have been found in Denmark in the Lake of Maribo, and in England in the county of Norfolk. With these constructions we must also connect the _crannoges_ or artificial islands of Ireland, the first of which was discovered in 1836 by Sir W. R. Wilde, a member of the Royal Academy of Dublin. Since this date various investigations have been made of these objects, and, at the present time, no less than fifty _crannoges_ have been discovered, distributed among the various counties of Ireland. [Illustration: Fig. 150.--Vertical Section of a _Crannoge_ in the Ardakillin Lake.] Most of these islets were composed of heaps of stones held together by piles, nearly in the same way as in the _ténevières_ in Switzerland; but the _crannoges_ differ from the latter in being raised above the water. Some of them, however, are formed by a collection of vertical piles and horizontal joists, constituting an external inclosure, and even internal compartments, inside which all kinds of remains were collected. This kind are called _stockaded_ islands. They are generally of an oval or circular shape, and their dimensions are always kept within rather narrow limits. In his work on 'Pre-historic Times,' Sir John Lubbock gives the above sketch of a _crannoge_ in the Ardakillin Lake.