Le, an arrondissement of the department of the Upper Loire, in France, extending over 779 square miles. It has fourteen cantons, 117 communes, and 122,450 inhabitants. The capital is the city of the same name, distinguished by the addition en Belay, which is situated on the river Borne. It is the seat of the departmental boards of government, and the see of a bishop. It contains 2950 houses, with 13,100 inhabitants, whose chief employment is lace-making, and the manufacture of cotton goods, especially muslins. It has also some manufactures of copper and iron wares, and of pottery. Long. 3.47.40. E. Lat. 45.2.41. N.

PUY DE DÔME, a department in the south of France, formed out of the ancient province Lower Auvergne. It extends in north latitude from 45.26. to 46.11. and in east longitude from 2.17. to 3.54. In extent it is 3389 square miles, and is divided into five arrondissements, and these into fifty cantons and 438 communes, containing by the last census 573,100 persons. It is bounded on the north by the department of Allier, on the east by that of the Loire, on the south by the Upper Loire and the Cantal, and on the west by the Corrèze and by the Creuse. It is an elevated district, covered with hills and mountains, with few or no plains, but some beautiful valleys, not very wide, through which the streams flow. One of the most picturesque of these vales is that of Limagne, which extends along both banks of the Allier, from the entrance of that river into the department, to its passage out of it. It is remarkable for its fertility. The roads are planted with large walnut and elm trees, the sides of the hills are covered with vines, and on the tops are ornamented with towns, villages, and castles. Some of the mountains in the northern part, the highest of which reach to about 4000 feet, have marks of volcanic origin, and are composed of basalt or of lava. In the south the elevations are greater, and that called the Puzzulana Mont d'Or is about 6300 feet. The chief river is the Allier, which comes out of the department of the Upper Loire, Pyrenees, is navigable in its course through Puy de Dôme, and receives the waters of various streams. There are several lakes in some of the districts, but none of them of any great extent. The climate is raw and variable on the mountains, but in the valleys it is mild, intensely hot in summer, and severely cold in winter; and occasionally most violent storms, accompanied with hail, are experienced in the most fertile of the valleys. The chief products, besides corn, of which there is a surplus for the supply of the neighbouring departments, are hemp, flax, wax, honey, fruit, especially cherries, walnuts, and wine. The last is abundant, but in general not highly estimated. The best is in the valley of Limagne; but even there the greater part of the produce of the vines is distilled into brandy. The nuts are so abundant that a great quantity of oil is made from them; and as fuel is scarce, many of the walnut trees are made use of for that purpose. There are mines both of iron and of coal, but they are not extensively worked. The manufactures are linen cloths, blond lace, silk stockings, some cotton, and thin woollens, ribbons, jewellery, leather, and paper. The population is so much beyond the means of employment, that a great number of labourers yearly go to the neighbouring department to procure work in summer, and return in winter with the wages which they have earned. The department elects four deputies to the legislature. It is in the diocese of Clermont, and under the judicial power of the courts of law at Riom.

PUZZULANA or Pozzolana Terra, is a grayish kind of earth employed in Italy for building under water. The best is found about Puteoli, Baia, and Cuma, in the kingdom of Naples, from the first of which places it derives its name. It is a volcanic product, composed of heterogeneous substances, thrown out from the burning mouths of volcanoes in the form of ashes; sometimes in such large quantities, and with so great violence, that whole provinces have been covered with it at a considerable distance. In the year 79 of the common era, the cities of Herculaneum, Pompeii, and Stabia, although at the distance of many miles from Vesuvius, were nevertheless buried under the matter thrown out during these dreadful eruptions. This volcanic earth is of grey, brown, or blackish colour, and of a loose granular, or dusty and rough, porous or spongy texture, resembling a clay hardened by fire, and then reduced to a gross powder. It contains various heterogeneous substances mixed with it. Its specific gravity is from 2500 to 2800, and it is in some degree magnetic; but it scarcely effervesces with acids, although partially soluble in them. It easily melts per se; but its most distinguishing property is, that it hardens very suddenly when mixed with one third of its weight of lime and water; and forms a cement which is more durable in water than any other. According to Bergman's analysis, a hundred parts of Terra Pozzolana contain from fifty-five to sixty of siliceous earth, twenty of argillaceous, five or six of calcareous, and from fifteen to twenty of iron. Its effects, however, in cement may perhaps depend only on the iron it contains. It is evidently a martial argillaceous marl that has suffered a moderate heat. Its hardening power arises from the dry state of the half-baked argillaceous particles, which makes them imbibe water rapidly, and thus accelerates the desiccation of the calcareous part; and also from the quantity and peculiar state of the iron and manganese which it contains, on which metals its properties chiefly depend. It is found not only in Italy, but also in France, in England, and elsewhere.