Although hot-springs exist in most of the valleys of the Pyrenees yet there is no appearance of volcanic action In the structure of the mountain's, the mass of which to composed of primitive, transition, and secondary formations. The primitive rocks, which form the leant part of the mass, comprise granite and gneias; these rocks in the eastern part of the Pyrenees are found on the north doper considerably below the crest of the chain, but towards the west they form the crest Itself and part of the southern slope. Towards the middle of the rash° micaceous schist Is found and primitive limestone extends between the Garonne and the Ariege. Sienite, porphyry, serpentine, and trap are occasionally met with among the varieties of the primi tive formations. The transition rocks, which form the larger part of these mountains, are clay-slate and grauwacke-slate,which extend in two beds from one end of the chain to the other, resting in a very inclined position upon the primitive formations. Bands of red-sandstone and alpine limestone occur along the chain chiefly on the southern slope, and also nearly uninterruptedly on the northern slope, but not in such great masses. Ophite is found, not in strata, but in isolated masses, generally at the entrance of the valleys. The Pyrenees are rich in iron-ore; copper also, lead, and silver exist in the mountains that flank the valley of Baigorry ; some gold is washed down by the Salat, the Ariege, and the Garonne. Fine statuary and beautiful coloured marble are quarried.
The most important, because most practicable, passes of the Pyrenees are, proceeding from east to west, the Col-de-Pertus commanded by the fortress of Bellegarde, through which runs the road from Perpignan to Barcelona, practicable at all seasons, and for vehicles of every kind ; the Col-de-la-Perehe, commanded by the fortress of Mont-Louis, com municating between French and Spanish Cerdagne : the Port-de-Sale, through which runs the road from Toulouse and St.-Girons to Lerida :
the Port-de-Viella, by which communication is kept up between the valley of Arran and the rest of Spain : the Port-de-Caufranc, through which runs the road from Oldron by the valley of Aspe to Jam : the Port of Orisson and the Port of Roncevaux, or Roncesvalles, through which runs the road from St.-Jean-Pied-de-Port to Monreal : and tho Port-de-Maya, communicating between Bayonne and Pampelutia. The main road from Paris, Bordeaux, and Bayonne to Madrid crosses the Bidaszioa near the sea, at the western extremity of the chain. It was by the Pass of Pertus that the armies of Hannibal and Julius Caesar crossed the Pyrenees. Charlemagne advanced into Spain, si.n. 778, by the pass of lioncesvalles, where his rear-guard suffered great loss from the hardy mountaineers. Among the slain was the renowned Roland, whose name.still lives in the traditions of the country, besides being given to the famous Breche-de-Roland, the highest pass of the Pyrenees (about 9000 feet), which he is said to have formed by a blow of his sword. There are above 50 passes in the Pyrenees, but except those mentioned (not including the Breche-de-Rolcuid) few are traversed unless it be by smugglers or adventurous tourists.