Page:The New International Encyclopædia 1st ed. v. 03.djvu/225

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BLOUNT. 195 BLOWING-MACHINES. mcanor entirely inconsistent with his public trust and duty." The pro-British scheme caused much excitement at the time, both in and out of Congress, and lias since l)een knowTi as •Hlounf.s Conspiracy.' His formal trial was postponed until 1798, and early in 1700 the Senate decided to dismiss the imjjeachment on account of a lack of jurisdiction. Blount not then being a mem- ber. The whole incident increased considerably Blount's popularity in Tennessee, and soon after his expulsion he was elected to the State Senate, over which he presided for some time. Consult an article by Jlrs. JI. J. Lamb, in Magazine of Jhicrican u'lstor;/. Vol. XIII. (New York, 1884). BLOUSE, blouz (of uncertain origin). A name borrowed from the French for the loose, sack-like over-garment which, as worn in Eng- land by wagoners and farm laborers, is called a smock-frock. The English smock-frock is made of coarse and unbleached linen, sometimes plaited and embroidered. In Germany it is frequently tightened to the body by a belt, and is sometimes made of coarse woolen. France is preeminently the country of blouses. There they are worn universally by the laboring classes in tow^ls. and so characteristic is this garment that the French populace are often called the 'Blouses.' The ichite blouse is a Sunday dress with the working classes in France, and has often sered as a coun- tersign among the leaders of sections in secret societies. BLOW, bio, John (1648-1708). An English composer and musician; bom (probably) at North Collingham (Xottinghamshire) . He was trained in nmsic as one of the children of the Chapel Royal under Capt. Henry Cooke. In 1669 he was appointed organist of Westminster Abbey, and in 1085 composer-in-ordinary to James II. From 1687 to 1603 he was master of the choristers at Saint Paul's Cathedral, and in ,1699 became composer of the Chapel Royal. He published Lessons for the HarpsicJtord (1698) and a collection of songs entitled Amphion Angli- cus (1700). His other works, mostly unprinted, comprise fourteen services, about a hundred an- thems, sacred songs, and many odes, including the setting for Drvden's ode on the death of Pur- cell (160.5). BLOWFLY. See Fle.sh-Fi.y. BLOWGUN. A weapon used both for war and hunting by the tribes formerly inhabiting the Gulf region of the United States, by the na- tives of equatorial South America, and by the Malays of the East Indies. It consists of a straight tul)e from eight to twelve feet in length, from which a light arrow is forcibly expelled by the breath. The tube is made of a hollow reed or cane, the joints of which have been boied or burned through, or from two pieces of wood hol- lowed out and fitted together in llute fashion. In South America the arrow is usually tipped with poison, so that a slight scratch will produce death or paralysis, .-mong the Cherokees tiie arrow is feathered with thistle-dowTi, put on so as to fill the bore of the tube. BLOWING-MACHINES. Mechanical con- trivaiiics for ]>rii(lu(ing an artificial current of air, often of considerable intensity. For the pur- pose of description, blowing-machines may be divided into the following classes or tj-pes: (1) bellows; (2) piston blowers; (.3| fan blowers; (4) rotary blowers; (5) jet blowers. Bellows. Some form of bellows was probably the earliest form of blowing-machine. A very primitive form of bellows is still in u.se in some Eastern countries, consisting simply of the skin of some animal sewed into a rude bag, with a valve and nozzle. The older forms of domes- tic bellows are all constructed on the same prin- ciple — viz. a chamber formed of two boards with llexible leather sides, having at one end a nozzle with a narrow mouth; and in the lower board a valve of considerably larger area for the admis- sion of air. When the Iwllows are distended by drawing the boards apart, air is sucked in by tile valve, to replace the vacuum which would otherwise be formed, and then, when the boards are being closed, the valve, which only opens inward, is shut by the compressed air; and the latter, having no other escape, is forced out at the nozzle. The great fault of the common bel- lows is that it gives a succession of puffs and not a continuous blast. A former remedy for this was to use two bellows, so that one w'as blowing while the other was filling; but it was afterwards found that the double bellows secured a still more uniform blast. This machine is merely the common bellows, with a third board of the same .shape as the other two placed be- tween them, so as to form two chambers instead of one. The middle board is fixed, and both it and the lower one have valves placed in them opening inward. A weight on the lower board keeps the under chamber filled with air; and when this board is raised by a lever or other- wise, the air which it contains is forced into the upper chamber. The exit-pipe is attached to the latter, and a weight is placed on the upper board sufficiently heavy to press the air out in a con- tinuous stream, the continuity being maintained by the large quantity of air always present in the upper chamber, and the uniform pressure of the weight. Sometimes a spring is used instead of a weight to press out the air. This is the usual construction of the ordinary blacksmith's bellows. Even with the double bellows, however, the constant refilling of the upper portion from the lower prevents the blast from being quite regular, and its use is therefore limited to such simple requirements as are furnished by black- smiths' forges and domestic fireplaces. Piston Blowers. The Chinese bellows is one of the earliest and simplest forms of piston blowers. It consists of a square chamber of wood, with a close-litting piston, which, when drawn back, sucks air in through a flap valve like the ordinary bellows-valve, and when pushed forward compresses this air and forces it out through a nozzle. The modern form of piston blower is virtually an air-pump or compressor for producing low pressures. ( See Air-Compres- SORS. ) Its most extensive use is for supplying the air-blast to blast-furnaces, Bessemer con- verters, etc. Steam is the power most com- Monly used; but gas-engines have recently been introduced, and any other power, such as a fall of water, may be employed. . blowing-engine of nodern construction usually consists of a steam- cylinder and an air-eylindir set tandem, either vertically, one above the other, or horizontally, one ahead of the other, with a common piston- roa and a heavy ily-wheel to regulate the opera- tion. Tlip air-cylinder is usually jilaccd upper- n'Ost in :i vertical engine ami fiucmost in a hori- zontal engine, and the air is usually compressed