E U K O P 689 of Huelva (of which the latter is capable of yielding 500,000 tons of iron pyrites annually). More than a third of all the zinc obtained in Europe is contributed by Belgium, and nearly as much is furnished by Germany. The principal Belgian mines are in the province of Liege, and the principal German mines at Oppeln in Upper Silesia. Tin is found only in a few localities. The richest mines ar those of Cornwall in England, which have been worked from the earliest historic period ; and next in importance are the Austrian mines in the Erzgebirge. Mercury is practically peculiar to Spain and Hungary, though it is obtained in small quantities at Yallalta in the Italian province of Belluno, at Santa Fiora in the province of Grosseto, and in Germany at Deuxponts in the Pala tinate, and is also known to exist in Bosnia and Roumania. The principal Austrian mines are at Idria in Carniola, and the principal Spanish mines at Almaden and Ahnadalejo in Ciuclad Real. The salt production of Europe amounts to about 95,000,000 or 100,000,000 cwt. per annum. To this total no contri bution is made by Finland, Sweden, Denmark, Luxem bourg, Belgium, Servia, or Montenegro. It is partly pro cured from mines, partly from springs, and partly from salt lakes and the ocean. The most productive mines are in the Carpathians (at Wieliczka and Bochnia in East Galicia), and at Salzburg on the north side of the Alps; there are also extensive deposits in Chester and Worcester in England, in the departments of Upper Saone and Ariege in France, at Wilhelmsgliick and Friedrichshall iu Wiirtemberg, at Berchtesgaden in Bavaria, at Leo- polclshall in Anhalt, at Stassfurt and Erfurt in Prussian Saxony, at Stettin in Hohenzollern, and at Sprunberg in Brandenburg, at Cardona, Pinoso, Gerry y Villanueva, in Spain, and in the districts of Prahova, Valcea, and Bacau in Roumania. Salt springs are still more widely distributed. Bay salt is largely manufactured in France, both on the Mediterranean and Atlantic seaboards ; in Russia, along the coasts of the Black Sea ; in Spain, at Cadiz and Torrevioja, itc. : in Italy, in Sardinia, Sicily, and Elba ; in Turkey, at the mouth of the Danube, and in the island of Crete ; and in Greece, in the island of Santa Maria. The salt lakes of Bessarabia alone yielded on an average 13,924,000 cwt, yearly from 1819 to 1850, and carriers come for supplies from Poland, Volhynia, Kieff, and Teheniigoff. About 230 waggons are loaded daily in the season. 1 Full details on the European coal-fields have already been given in the article COAL, vol. vi. p. 55-58 ; and the reader will find a similar account of the iron mines under IRON. Sulphur mining is one of the greatest industries of Italy and Sicily, forming, indeed, almost the exclusive means of support for Girgenti and some other towns ; graphite is obtained in Bohemia and Moravia, Bavaria, England, Russia, Sweden, and Spain ; alum more particu larly from Scotland, Bohemia, Germany, Russia, and Spain ; asphalte from Switzerland, Italy, Brunswick, Dal- matia, and Tyrol; and petroleum from the Carpathian mountains, Alsace, Lorraine, France, ifec. The four great determining facts in regard to the climate of Europe are these : its northern borders are within the Arctic circle ; in the south its most southern points are 9 degrees of latitude from the tropic of Cancer ; to the east extends for 5000 miles the continuous land surface of Asia ; to the west lie the waters of the Atlantic. Of minor but by no means small importance are the presence of the Medi terranean along the south, and the peculiar character of the African continent. To the ameliorating influence of the 1 See " Ueber die Bessarabiselien Salzseen," in Z. fur Berlin. ]859. Enlk zu ocean must be ascribed the main features that distinguish the climate from that of the corresponding portions of Asia, and assimilate it so largely to the insular type. Like other great masses of water, the Atlantic is less exposed to rapid thermometric oscillations than the surface of the land, and its contiguity tends to produce a similar stability. Slowly but continually it is surrendering the heat which it has gathered in the regions of the sun. Though no problem of physical geography is more keenly debated than the method by which the heat is conveyed and distributed, the fact is ad mitted on all hands that such conveyance and distribution does take place. Part of the work is done directly by means of currents, part indirectly by means of winds. The questions in dispute are mainly what are the currents, how are they produced, and what is the area of their individual influence ? While one physicist ascribes all the credit to the Gulf Stream, another argues that the Gulf Stream has spent both its impetus and its heat long before it approaches the European seas, and that its contributions, if there be any at all, are altogether infinitesimal. Be that as it may, the influence of the ocean as a whole is easily verified ; a glance at a map with isothermal lines at once indicates its extent. The line, for instance, of 36 of mean annual temperature, which in the east of the continent passes near Orenburg, reaches as far north as 73 in the sea between Iceland and Norway. As the complement to this stands the fact that the temperature of the East Spitzbergen Sea is still so high that no true polar ice finds its way further south than 75 N. lat, while on the American coast it is carried down to 36 N. lat. In other words, if the European conditions were the same as the American, instead of the polar ice never being seen at the North Cape, it would come sailing down past the straits of Gibraltar.- As regards its rainfall Europe belongs iu the main to Rainfall, the zone which is characterized by irregularity of seasonal distribution ; its southern portions to the sub -tropical zone distinguished by the dryness of its summers. The line of demarcation runs at a little distance to the north of the Spanish coast of the Bay of Biscay, continues along the northern slope of the Pyrenees, turns north-eastwards to the neighbourhood of Valence on the Rhone, curves south ward to Genoa, follows the line of the Northern Apennines, strikes across the Adriatic from Rimini to the neighbourhood of Zara, and proceeds by way of Seraievo, Novi-Bazar, and Sofia to the coast of the Black Sea, south of Zozopoii. Within the sub-tropical zone the maximum rain fall occurs during winter in the south of Spain and Italy ; during autumn and spring in central and northern Spain, the south of France, and northern and central Italy. In the zone of irregular distribution Scotland, Ireland, and western England have their maximum iu winter; western France, eastern England, the coast regions of the Low Countries and Denmark, and the greater proportion of Nor way have theirs in the autumn; while in eastern France, the German Empire, Austria, Hungary, Russia, and Sweden it falls in summer. The general conditions that determine the quantity of rain in a given district are well known, the height and direction of the mountains, proximity to the coast, and so on. As most of our rain is brought by south west and west winds, the western parts of the continent have on the whole a heavier rainfall than the eastern ; though to the south of the Alps and the Pyrenees the relief of the peninsulas, and the presence of such a large secon dary reservoir of evaporation as the Mediterranean, produce great irregularities. The following statistics show the in fluence of a western position : - See Petermann s Mitthcilunrjen, 1877, p. 24, and the works of Carpenter, Troll, Dove, and BuchaD.
VTTI. _ ,97