Austrian and Russian troops, and Frederick's ultimate expulsion seemed only a question of time. Yet the Prussian king recovered his lost ground by gigantic efforts and eventually retained his Silesian territory undiminished.
The annexation by Frederick was followed by a complete reorganization in which the obsolete powers of the local dynasts were abolished and Silesia became a mere province of the highly centralized Prussian state. Owing to the lack of a corporate Silesian consciousness and the feebleness of their local institutions, the people soon became reconciled to their change of rulers. Moreover Frederick, who had proved by his wars the importance which he attached to Silesia, was indefatigable in times of peace in his attempts to justify his usurpation. Making yearly visits to the country, and further keeping himself in touch with it by means of a special " minister of Silesia," he was enabled to effect numerous political reforms, chief of which were the strict enforce- ment of religious toleration and the restriction of oppressive seignorial rights. By liberal endowments and minute but judicious regulations he brought about a rapid development of Silesian industries; in particular he revived the mining and weaving operations which at present constitute the country's chief source of wealth.
After its incorporation with Prussia Silesia ceases to have an independent political history. During the Napoleonic wars it was partly occupied by French troops (1806-1813), and at the begin- ning of the War of Liberation it was the chief scene of operations between the French and the allied armies. In 1815 it was enlarged by a portion of Lusatia, which had become detached from Silesia as far back as the nth century and since then had been annexed to the kingdom of Saxony. During the rest of the 19th century its peace has been interrupted from time to time by riots of discontented weavers. But the general record of recent times has been one of industrial development and prosperity hardly inferior to that of any other part of Germany.
See C. Griinhagen, Geschichte Schlesiens (2 vols., Gotha, 1884- 1886), and Schlesien unter Friedrich dem Grossen (2 vols., Gotha, 1 890-1892) ; M. Morgenbesser, Geschichte von Schlesien (Berlin, 1892) ; Knotel, Geschichte Ober schlesiens (Kattowitz, 1906) ; H. Grotefend, Stammtafeln der schlesischen Fiirsten bis 1740 (Breslau, 1889); F. Rachfahl, Die Organisation der Gesamtstaatsverwaltung Schlesiens vor dem dreissigjdhrigen Kriege (Leipzig, 1894); H. Fechner, Geschichte des schlesischen Berg- und Hiittenwesens 1/41-1806 (Berlin, 1903) ; see also the Zeitschrift des Vereins fur Geschichte und Altertunt Schlesiens (Breslau, 1855 sqq.), and Oberschlesische Heimat, Zeit- schrift des ober schlesischen Geschichtsvereins (Oppeln, 1905 sqq.).
Austrian Silesia.
Austrian Silesia (Ger. Osterreichisch-Schlesien) is a duchy and crownland of Austria, bounded E. by Galicia, S. by Hungary and Moravia, W. and N. by Prussian Silesia. It has an area of 1987 sq. m. and is the smallest province of Austria. Silesia is divided by a projecting limb of Moravia into two small parts of territory, of which the western part is flanked by the Sudetic mountains, namely the Altvater Gebirge; while the eastern part is flanked by the Carpathians, namely the Jablunka Gebirge with their highest peak the Lissa Hora (4346 ft.). A great pro- portion of the surface of Silesia is occupied by the offshoots of these ranges. The province is traversed by the Vistula, which rises in the Carpathians within eastern Silesia, and by the Oder, with its affluents the Oppa and the Olsa. Owing to its mountain- ous character, and its slopes towards the N. and N.E., Silesia has a somewhat severe climate for its latitude, the mean annual temperature being 50 F., while the annual rainfall varies from 20 to 30 in.
Of the total area 49-4% is arable land, 34-2% is covered by forests, 6-2% by pasturages, while meadows occupy 5-8% and gardens 1-3%. The soil cannot, as a rule, be termed rich, although some parts are fertile and produce cereals, vegetables, beetroot and fruit. In the mountainous region dairy-farming is carried on after the Alpine fashion and the breeding of sheep is improving. Large herds of geese and pigeons are reared, while hunting and fishing constitute also important resources. The mineral wealth of Silesia is great and consists in coal, iron-ore, marble and slate. It possesses several mineral springs, of which the best known are the alkaline springs at Karlsbrunn. Like its adjoining provinces, Silesia boasts of a great and varied industrial activity, chiefly represented by the metallurgic and textile industries in all their branches. The cloth and woollen industries are concentrated at Bielitz, Jagerndorf and Engelsberg ; linen is manufactured at Freiwaldau Freudenthal and Bennisch ; cotton goods at Friedek. The iron industry is con- centrated at Trzinietz, near Teschen, and various industrial and agricultural machines are manufactured at Troppau, Jagerndorf, Ustron and Bielitz. The organs manufactured at Jagerndorf enjoy a good reputation. Other important branches of industry are chemicals at Hruschau and Petrowitz; sugar refineries, milling, brewing and liqueurs.
In 1900 the population numbered 680,422, which corresponds to 342 inhabitants per sq. m. The Germans formed 44-69% of the population, 33-21% were Poles and 22-05% Czechs and Slavs. According to religion, 84-73 were Roman Catholics, 14% Protestants and the remainder were Jews. The local diet is composed of 31 members, and Silesia sends 12 deputies to the Reichsrat at Vienna. For administrative purposes Silesia is divided into 9 districts and 3 towns with autonomous munici- palities: Troppau, the capital, Bielitz and Friedek. Other principal towns are: Teschen, Polnisch-Ostrau, Jagerndorf, Karwin, Freudenthal, Freiwaldau and Bennisch.
The actual duchy is only a very small part, which was left to Austria after the Seven Years' War, from its former province of the same name. It formed, with Moravia, a single province until 1849, when it was created a separate duchy.
See F. Slama, Osterreichisch-Schlesien (Prague, 1887); and A. Peter, Das Herzogtum Schlesien (Vienna, 1884).
SILESIAN WARS, the name given to the contests between
Austria and Prussia for the possession of Silesia. The first (1740-
1742) and second (1 744-1 745) wars formed a part of the great
European struggle called the War of the Austrian Succession
(q.v.), and the third war (1756-1762) similarly a part of the Seven Years' War {q.v.).
SILHOUETTE, ETIENNE DE (1709-1767), controller-general
of France, was born at Limoges on the 5th of July 1709. He
travelled extensively while still a young man and drew attention
to himself by the publication of English translations, historical
writings, and studies on the financial system of England. Suc-
cessively councillor to the parlement of Metz, secretary to the
duke of Orleans, member of the commission on delimitation of
Franco-British interests in Acadia (1749), and royal commis-
sioner in the Indies Company, he was named controller-general
through the influence of the marquise de Pompadour on the
4th of March 1759. The court at first reposed a blind confidence
in him, but soon perceived not only that he was not a financier
but also that he was bent on attacking privilege by levj'ing a
land-tax on the estates of the nobles and by reducing the pensions.
A storm of opposition gathered and broke: a thousand cartoons
and jokes were directed against the unfortunate minister who
seemed to be resorting to one financial embarrassment in order
to escape another; and in allusion to the sacrifices which he
demanded of the nobles, even the conversion of their table plate
into money, silhouette became the popular word for a figure
reduced to simplest form. The word was eventually (1835)
admitted to the dictionary by the French academy. Silhouette
was forced out of the ministry on the 21st of November 1759 and
withdrew to Brie-sur-Marne, where during the remainder of
his life he sought refuge from scorn and sarcasm in religious
devotion. He died on the 20th of January 1767.
Silhouette left, several translations from the English and the Spanish, accounts of travel, and dull historical and philosophical writings, a list of which is given in Querard, France litteraire, ix. 138. A Testament politique, published under his name in 1772, is apochryphal. See J. P. Clement and A. Lemoine, M. de Silhouette (Paris, 1872).
SILICA, in chemistry, the name ordinarily given to amorphous
silicon dioxide, SiO2. This chemical compound is widely and
most abundantly distributed in nature, both in the free state and
in combination with metallic oxides. Free silica constitutes the
greater part of sand and sandy rocks; when fairly pure it occurs
in the large crystals which we know as quartz (q.v.), and which,
when coloured, form the gem-stones amethyst, cairngorm,
cats'-eye and jasper. Tridymite (q.v.) is a rarer form,
crystallographically different from quartz. Amorphous forms also occur:
chalcedony (q.v.), and its coloured modifications agate, carnelian,
