BOYLE'S LAW
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BRACT
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German at Cornell University, and then accepted the chair of Germanic languages and literature at Columbia College, a post which he held until his death. Among his chief works are A N or sent an's Pilgrimage; Gunnar, a Norse Romance; Goethe and Schiller, their Lives and Works; Essays on German Literature; and a Commentary on the Writings of Henrik Ibsen.
Boyle's Law is an answer to the following question: "Just how does the volume of a given mass of gas vary when the pressure is varied and the temperature held constant?" This query was first definitely answered by Robert Bbyle, a distinguished English physicist, in his essay on A Defense of the Doctrine Touching the Spring and Weight of the Air, published at London in 1772.
He inclosed a definite mass of air in the closed arm of a U-tube, as shown in the figure. He varied the volume, V, of this inclosed gas by pouring in more and more mercury; and measured the
Eressures, P, corresponding. Q this way Boyle found that so long as the mass and temperature remain constant, the product of the pressure by the volume is a constant. This fact is known as Boyle's law, and may be expressed algebraically as follows :_^
PV=K
where K =-a constant.
Boyne, a river of Ireland, emptying into the Irish Channel after a course of about 80 miles. It has been called the Boyne of Science, because of the many institutions along its banks. It is celebrated for its scenery no less than for its historical associations. On its banks was fought, July i, 1690, the famous battle of the Boyne, in which William III utterly routed James II. An obelisk, 150 feet in height, marks the scene of the battle.
Bozzaris (bot'sa-res or boz-zar'is}, Marco, a Greek patriot, was born about 1788, at Suli, in the mountains of Epirus. His whole life was spent amid the din of battle. Driven from Suli, he united with a number of other refugees in the. Ionian Islands.
BOYLE S EXPERIMENT
against Turkey, and entered first the French service. In 182^ AH Pasha, an Albanian, took arms against Turkey, and Bozzaris, with several hundred followers, joined him and won several victories. After the death of AH Pasha, Bozzaris carried on the war for a while successfully. Later he became a general in the Greek army. When this army withdrew to Missolonghi, Bozzaris skillfully defended the place. In 1823 a Turkish army of 13,000 marched against the Greeks, and Bozzaris led 1,200 men to meet it. On August 20 he came upon the camp of the vanguard of the enemy, 4,000 strong. At night, leading 350 men, he burst upon his startled foes, and routed them with great slaughter. Bozzaris was killed while leading his men to the final attack, in Aug., 1823. The story of this heroic fight has been told by Fitz-Greene Halleck, in his poem, Marco Bozzaris.
Brabant (bra'bant), a district in the lowlands of Holland and Belgium, and now forming parts of these two kingdoms. In the course of its history it has had many masters. In 1814, by the treaty of Paris, it became a part of the Netherlands, and was divided in 1830 into the provinces of North Brabant, South Brabant and Antwerp. The Belgian revolution, in 1830 left North Brabant with the Netherlands, while the other two parts fell to Belgium. North Brabant (area, 1,980 square miles), with 'sHertogenbosch as its capital is a little larger than Rhode Island, and has a population of 597,538 South Brabant, somewhat smaller in size (area, 1,268 square miles), has over one and a quarter million people, speaking Flemish, and is one of the most densely inhabited countries in Europe. It is highly cultivated, and has important manufactures. Its capital is Brussels. Brabant or Brussels lace is well known. See ANTWERP.
Brace, Charles Loring, an American author and traveler, noted for his benevolent labors, was born at Litchfield, Conn., in 1826, and died in the Tyrol, Switzerland, Aug. n, 1890. He worked among the lowest classes .in New York, and was the founder of the Children's Aid Society in 1853, which has provided country homes for over 60,000 children. He traveled considerably in Europe, studying especially reform schools and prisons. He published several volumes of Travels, Short Sermons for Newsboys and a work on The Dangerous Classes of New York.
Bract, a general name applied to leaves, usually much reduced, ewhich occur in a flower cluster. The word is somewhat extended in application by calling any reduced leaf-like body bract-like. For example, the sepals of a flower are often spoken of as bract-like.
HJALMAR HJORTH BOYESEN
