BOHEMIA
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BOILEK
Bohe'mia, formerly one of the kingdoms of Europe, now the most northern province of the Austro-Hungarian monarchy. It has an area of 20,060 square miles, or considerably less than West Virginia, and a population of 6,318,697. It contains nearly 400 cities, of which the largest is Prague, the capital of the kingdom and third city of the empire, with a population of 201,589. The country is enclosed on all sides by lofty mountains, which abound in mineral wealth, silver, tin, copper, iron, porcelain, clay, etc., while more coal is mined in the kingdom than in all the other provinces of the Austrian empire. The Elbe and its numerous branches water the soil, and grains and fruits are extensively raised. Its manufactures are important; dyeing and calico printing, linen making and flax spinning, glass works (which afford work to 27,000 persons) being among the principal industries. The Elbe and Moldau, an extensive canal, good roads and a system of railroads of nearly 3,000 miles in extent supply the means of carrying on a large transit trade. The people are mainly Czechs, Germans and Jews. Among them education is much more wide-spread than in any of the other provinces of Austria. The University of Prague has over 3,000 students, and there are a large number of other schools. Bohemia sends no members to the lower house of the Austrian reichsrath or parliament of the western part of the empire. It has a provincial diet of 242 members, competent to legislate on all matters not reserved to the reichsrath. The Czechs, a Slavic race, •came into the country as early as the 5th century, A. D., driving out the earlier inhabitants. From that time Bohemia came under the power of various nations, and was at one time an elective kingdom; but in 1526 it became a part of Austria, and its history since that time has merged with that of Austria. There has been for some years a continual struggle between the Germans and the Czechs for supremacy. The Czech language is one of the most cultivated of the Slavonic dialects, and recently there has been a revival in its study as well as in Bohemian literature. The martyr John Hus was a Bohemian.
Boileau (bwd'lo'), Nicholas, a French poet and critic, was born at Paris in 1636, and after a thorough education took up writing as a profession. His first work was a satire, Adieu of a Poet to the City of Paris. He became a friend of Molidre, La Fontaine and Racine, and was pensioned by the king. His Art of Poetry is considered very fine.
He did much as a critic to purify and refine the French language, and has had a great influence on French literature. He was made a member of the French Academy. He died at Paris in 1711.
Boiler, an apparatus for generating steam by heating water. In its ordinary form it consists of the following parts: a furnace in which the fuel is burnt; a chimney or other means of producing a draught and of removing the products of combustion; a vessel containing the water, this vessel so arranged that the heat from the furnaces reaches the water; a steam space connected by pipes with the engine or other device in which the steam is used; a pump or injector for supplying the boiler witn water; various devices for safety and convenience of operation, such as steam-gauge to indicate the pressure of the steam, a water-gauge to indicate the amount of water in the boiler and a safety valve to release the steam if it is beyond a safe pressure.
Boilers have various forms, depending
BABCOCK AND WILCOX BOILER
upon the purposes and the conditions of their use. The object in each case is to produce with safety the greatest amount of steam at the least cost of fuel, of operation and of maintenance. In the earlier days pressures of only three or four pounds per square inch were used, but to-day 100 and 150 pounds are the common pressures for engines, and double these pressures can hardly be said to be uncommon. These higher pressures demand increased strength in the construction of the boilers. A few years ago cast and wrought iron were much used, but only steel is used in the best boilers today. The cylindrical form is universally used, as that is the strongest and most convenient form to stand internal pressure.
Boilers may be divided into two general types: (i) those in which the furnace and
