[Illustration: Bernard VII _d._ 1418 | +-------------------+-------------+ | | John IV Bernard, Count of _d._ 1473 Pardiac | _d._ after 1462 +---+-----+ | | | | John Charles Jacques d’Armagnac _d._ 1473 _d._ 1497 created Duc de Nemours _d._ 1477 | +----+-----+ | | John Louis _d._ 1500 _d._ 1503] For some way above Bordères the Neste of Luron traverses a gloomy ravine; but then all at once it opens out and we come on a basin well cultivated, fringed with woods, and studded with twelve villages, about their church spires. The road ascends steeply past slate quarries that send down their avalanches of grey refuse over the base of the hill surmounted by the donjon of Gélos. It is still a long way on to the Lac de Caillaouas, that lies at the height of 3500 feet, and covers 120 acres; its blue waters are fed by some small tarns higher up under the glaciers of the Gourgs Blancs. This is one of the scenes of most savage grandeur in the Pyrenees. The lake is of great depth, and swarms with trout. A tunnel has been driven fifty-five feet below the surface through the rock that retains the lake, and through this the water can be drawn off to supply the deficiencies in the Neste and the canal that leads from it in time of drought. The work was completed in 1848. The other Neste, that of Aure, is of even more economic importance. It rises under the Pic de Campbieil, 9550 feet; but receives a large influx of water from the Neste de Couplan that is supplied from a whole series of lakes, the largest of which is Orredon.