"The most elevated of an extensive system of volcanic rocks, resting partly on granite or gneiss, and in part on the Jurassic formation, which by their position and constitution prove themselves to be the remains of a single and powerful volcano, of the same character as those in the Mont Dore and Cantal. Its products, however, are disposed in a somewhat different manner, being spread over an almost equally extensive surface without accumulating into such mountainous masses around their centre of eruption. Two causes seem to have contributed to occasion this diversity of aspect, namely: first, that the eruptions of this volcano appear to have been less frequent than in the other instances; secondly, that its lavas consist either of basalt or clinkstone almost exclusively. They therefore were possessed of great comparative fluidity; and having burst out on one of the highest eminences of the primary platform, which afforded a considerable slope in most directions, they appear to have flowed to great distances immediately upon their protrusion from the volcanic vent. "We shall be fully justified, by the universal declination of these volcanic beds from the Mont Mézenc, in fixing the site of the eruptions in its immediate proximity; and on the south-east of this rocky eminence, in the vicinity of the Croix des Boutières, there still exists a semicircular basin whose steep sides are entirely formed of scoriæ and loose masses of very cellular and reddish-coloured clinkstones." The desolate tableland over which one travels to reach Mézenc is well described by Georges Sand in her novel _Le Marquis de Villemer_, and the backward and unprogressive character of the inhabitants has not altered since her time. The carriage is left at the village of Les Estables, a poor and dirty place, where the natives shiver through half the year. Their condition is indeed miserable. Their cottages, built of lava-blocks, are thatched with straw, or roofed with clinkstone (_phonolith_). The street is filthy, encumbered with stones and deep in slime. Were it not for the lace industry and for the violet harvest, the place would be deserted. The cattle are lean and poor in quality, from lack of lime in the soil; the harvests ripen so late that when gathered in the crops are frequently spoilt.