The typical Dutch windmill is composed of four long sails at right angles to each other, fixed on an axis inclining about 10° to the horizontal and mounted on an inclosed tower of masonry or wood. Modifications of this type include six or more sails. The web of the sails is generally of canvas, but wood may be substituted. In the best forms of European windmills each sail is composed of arms or whips 30 feet or more in length, attached at right angles to the sail axle. Transverse bars or rods are secured to the whip at intervals throughout its length, and on these the sails are stretched. By setting the bars at varying angles with the plane of revolution of the whips, a warped surface is produced. This is essential, since the sails revolve in a plane at right angles to the direction of the wind, so if the surface was not curved the only effect of the wind would be to press against a fixed surface. The width of the sails is generally greater at the outer than at the inner extremity, and the total sail area is smaller in proportion to the area of the wind zone than is the case in American mills. American windmills may be divided into two broad classes: (1) those that revolve in the same direction as the wind and resemble paddlewheels or certain types of water wheels, and (2) those revolving at right angles to the wind. The members of the second class in this one respect are similar to the Dutch and European mills already described, and may for convenience be I called sail wheels. Most of the windmills in use fall in the second class. The paddle-wheel mills must have one-half of their fans guarded from the action of the wind, for otherwise they will not revolve, since the pressure on the two halves will balance. This protection may be afforded, in the case of wheels revolving on a horizontal axis, by casing in the lower half of the wheel; and for wheels on a vertical axis, by either casing in one-half or by using folding themselves when they come into the counter-pressure. In either of these sub-classes, it is evident that only a portion of the total wind area of the wheel is effective. vanes that close on strong tendency for the wheels to revert to a simple form, somewhat like the old European mills, except that in the place of a few curved sails of canvas and wood there are a number of metal sails with curved surfaces, all connected to make a compact, strong wheel. Whatever the type of mill employed, its highest efficiency can be attained only by keeping it constantly in the wind; that is, so that its plane of revolution will be at right angles to the wind in the sail-wheel mill, and parallel with it in the paddle-wheel type. In the early European mills the wheel and tower were mounted on a pivoted post and turned by hand. Later on the mills were so arranged that only the wheel, its accessories, and the dome or cap of the tower were turned. This was done either by hand or by wind power, an auxiliary windmill, with gearing, being employed in the latter case. the American mill, also, only the upper part of the mill revolves. The turntable to effect this movement is actuated by the direct pressure of the wind on either the wheel itself or a rudder attached to it; or else by means of a secondary wheel, which is used to turn the main wheel into the wind. In Besides devices to keep the wheel in the wind others must be employed to regulate the wheel under varying conditions of wind velocity. Such regulation is necessary to secure the maximum amount of power when the wind is low, a fairly constant speed, so far as is possible, under all conditions, a reduction of speed in high winds, and the complete stoppage of the windmill during gales. Regulation may be effected by applying a brake to check the speed, or, as is commonly the case, by diminishing the area of sail exposed to the wind. The latter may be effected by changing the angle of the groups of vanes of a seetional wheel, by means of centrifugal action applied through lever rods and resisted by means of weights or springs. The greater the velocity of the wheel the more the vanes will be turned until, if the wind be high enough, they offer it no purchase whatever. A second method involves turning the wheel partially or wholly out of the wind, by revolving it about the axis of the tower. Counterweights may also be used here, as in the case of both the centrifugal gov ernor and some of the devices used for holding the wheel in the wind. The object of the counterweights is to prevent too sudden action of the regulating devices, which might result in damage to some portion of the mechanism in volved. The horizontally set paddle-wheel mills are generally placed near the ground and facing the prevailing wind. They are of no use except when the wind blows their way. Sometimes the The chief use to which windmills are put in America is the pumping of water from wells, vanes are made in the form of a warped or screw surface to obviate this defect, whereupon the but they are also employed, often conjointly, for mill assumes somewhat of the sail-wheel type. grinding grain and cutting fodder for stock, turnIn the vertical paddle-wheel mills the wind guarding grindstones and other machinery for repairmay be made in the form of a semi-cylindrical revolving hood, self-adjusting by means of the changing direction of the wind itself, through the action of the wind on a rudder. The American sail-wheel windmills vary in design from four or more arms attached to a horizontal axis, with a single plain board nailed to the arm at such an angle as to catch the wind, to an elaborate series of fans in one or more annular rings, the fans being composed of narrow slats of wood, also set at an angle with the wind. From this complex type there is a ing and making farm tools, and numerous other purposes where a relatively small amount of irand a minimum of expense for maintenance and regular power is needed and where low first cost operation are essential. The power of windmills increases a little faster than the square of the wind velocity and about 1.25 times the square of the diameter of the wind wheel. According to Murphy (see bibliography below) "a good 12-foot stel mill should furnish one horsepower in a 20-mile wind (indicated) and 1.4 horsepower in a 25mile wind. This is the smallest amount of power that will do any considerable amount of useful work. A 16-foot mill will furnish 1.5 horsepower in a 20-mile wind (indicated) and 2.3 horsepower in a 25-mile wind. "A 12-foot steel mill and a 50-foot steel tower as commonly made weigh about 2000 pounds. A 16-foot steel mill and a 50-foot steel tower weigh about 4250 pounds. The 16-foot outfit weighs more than twice that of the 12-foot, and its power is only 1.5 that of the latter. In addition, the 12-foot mill will govern more easily and is less likely to be injured in a storm than the 16-foot mill. In most cases, therefore, it is better to use two 12-foot mills than one 16-foot mill." "Steel mills," he says, "with few large sails, have much more power than the wooden mills with their many small sails." Mills should be placed on towers 50 to 70 feet high, in order to get them at least 30 feet above the tallest trees and buildings. Mills should start in as light a wind as corresponds to a velocity of four or five miles per hour. For information as to velocity and other phases of the wind, see WIND. BIBLIOGRAPHY. Consult: Wolff, The Windmill as a Prime Mover (New York, 1885), a technical treatise; Perry, Experiments with Windmills; Barbour, Wells and Windmills in Nebraska, which contains a very interesting descriptive review of home-made windmills; and Murphy, The Windmill: Its Efficiency and Economic Use, also mentioned above (Washing ton, D. C., 1899, 1899, and 1901, being Nos. 20, 29, and 41-42, respectively, of Water Supply and Irrigation Papers of the United States Geological Survey). WIN'DOM, WILLIAM (1827-91). An American legislator and Cabinet officer, born in Waterford, Belmont County, Ohio. He was educated at Mount Vernon (Ohio) Academy, was admitted to the bar in 1850, and in 1852 was elected prosecuting attorney of Knox County on the Whig ticket. In 1855 he removed to Winona, Minn., where he allied himself with the Republican Party. He was a Republican member of Congress from 1859 to 1869, and was chairman of the important Committee on Indian Affairs. In July, 1870, he was appointed to the seat in the United States Senate made vacant by the death of Daniel S. Norton, and was regularly elected in 1871 and again in 1877, holding the position of chairman of the Committee on Appropriations. On March 4, 1881, he resigned his seat to enter the Cabinet of President Garfield He WINDOW (Icel. vindauga, window, wind-eye, from vindr, AS. wind, wind+auga, Goth. aug5, OHG. ouga, Ger. Auge, AS. éage, Eng. eye). An opening in the wall of a building for the admission of light and air. Windows are generally closed with glass, set in a frame called the sash. This may be of wood or of metal, and may be fixed or arranged to be opened at will. Commonly the sash is in two halves, either hinged at the sides and meeting in the middle, as in French' and 'casement' windows, or sliding up and down in grooves, with cords and counterbalancing weights, as in 'double-hung' windows. The former are the more common on the Continent of Europe; the latter in England and the United States. The sash is, however, sometimes pivoted so as to turn horizontally or vertically. When stained glass is used, it is set in small pieces held together by grooved strips of lead, and stiffened by iron bars. Large windows are often subdivided by fixed vertical bars or mullions of wood, metal, or stone, and one or more horizontal bars called transoms. A bay window or cow window is one or a group of windows set in a frame or structure projecting outward from the face of the wall. A dormer is a vertical window lighting the interior of a steep roof. When the sash is made to lie in the slope of a roof it is called a skylight; it may be fixed or hinged, or partly fixed and partly hinged. In EGYPTIAN. It is sometimes asserted that windows were practically unknown until the Christian Era. This is a monumental error. In Egypt windows were in common use; in ordinary houses they pierced the wall on the second story front and on the inner court. In temple architecture they were rare, but occur at Karnak as clearstory openings in the hypostyle hall. military architecture they were common, and in the palaces and villas of the New Empire were elaborately treated with heavy stone jambs and sills, and lintels crowned with the characteristic cavetto cornice. The openings were protected by wooden slats and shutters. In Babylonia and Assyria there was little use made of windows, though some reliefs show clearstories lighting the larger and loftier palace halls. GREEK. In Greece windows were in use from prehistoric times, but remained quite simple rectangular openings, sometimes slightly smaller at the top: the window frame was of stone or of wood, as occasion required. in some cases the windows are oblong and double, the lintel being supported in the centre by a pier. The decorative framework of the opening was often not real, but carved in the wall masonry, as in the beautiful Erechtheion window. The windows, when not left as mere openings, were fitted with gratings of wood or metal, or with shutters (usually of wood), or with both. ROMAN. The Romans made even more use of windows, with greater variety of form and increased richness of decoration. In private houses those on the streets were ordinarily small and simple (e.g. house of John and Paul on the Cœlian, Rome), but windows of temples were often highly elaborate, e.g. in the temple of Vesta at Tivoli; at Palestrina, surmounted by a cornice resting on consoles; and in the little temple of the Deus Rediculus near Rome, framed with rich ornamental carving. Under the late Empire round-headed windows became common, as at Telmessos in Asia Minor. Of extraordinary beauty are the windows of the Porta dei Borsari at Verona, which with their pilasters and gables undoubtedly served as models for the masters of the Renaissance. The great halls of the therma were lighted by huge semicircular clearstory windows, fitted with elaborate bronze gratings. The use of glass was far commoner than is imagined, beginning even in Republican times and probably derived from Alexandria and Antioch. Even commoner was the use of transparent stones called specularia, the choicest of which came from Spain. EARLY CHRISTIAN, BYZANTINE, AND MOHAMMEDAN. The development of the basilical church involved the general use of windows, and many more actual examples have remained of this period, though they are far from being as beautiful as those of the Roman Empire. The normal brick window of Early Christian and Early Byzantine buildings was a single, plain and rather wide round-arched opening, without moldings or sculpture. Only in the East, where stone was commonly used, was the old GrecoRoman richness partly perpetuated, especially in the ruined cities of Central Syria, where hundreds, not to say thousands of windows remain in religious and secular structures built during the third, fourth, fifth, and sixth centuries A.D. As the Middle Ages approached the Byzantine windows took on new forms, and were slenderer, often with two lights, separated by marble colonnettes and framed with moldings. The Roman custom of filling the aperture with glass or transparent marble was continued and many examples remain of the perforated marble slabs; usually the perforations were small and circular, quite often square, sometimes in elaborate patterns. The perforations were at times filled with colored glass, thus combining the two varieties. The churches of Grado, Parenzo, Ravenna, Rome, etc., retain examples dating from the sixth to the eleventh century. In the Mohammedan East windows were early provided with musharabiyeh, lattice-work and stucco window sashes cut out in free and exquisite floral designs, filled with stained glass; this was practiced especially in Egypt (Cairo), but perhaps also in Syria, and many beautiful examples are to be seen in the mosques of Constantinople. Oc MEDIEVAL. Romanesque windows are ordinarily single, round-headed apertures, splayed where the wall is thick; very seldom does a twolight window with central colonnette occur. casionally the arched opening was framed with carving or treated, like the superb doorways, with receding arches and carved moldings, especially in Southern France and Southern Italy. But the highest development of the window came with the Gothic style. Its perfect system of balanced construction permitted the opening of windows as vast as the entire space between the supporting piers of a vaulted interior. Thus arose the magnificent pointed and circular windows with tracery (q.v.). dividing them into several narrow lights. They were filled with stained glass, which developed into an important branch of painting. For the first time-except for a few late Romanesque examples in France and Germany-the pieces of stained glass framed in lead were so assembled as to form immense figured compositions rivaling wallpaintings. France led the way, closely followed in this art by England and Germany. Italy was least important. RENAISSANCE. The discontinuance of the Gothic system of construction after the fifteenth century put an end to the use of tracery and reI moved the chief distinction between the windows of churches and secular buildings. The art of stained glass declined, although a few fine examples were produced in Florence and in Northern France during the early Renaissance. In general attention was now bestowed upon the architectural adornment and framing of the square or arched openings, which at first were single or coupled arches with little decoration, but later were enriched with most elaborate carved ornament, as in the superb windows of the Certosa at Pavia. In the later periods they were flanked by colonnettes and crowned with entablatures and often with curved or triangular pediments. Clear glass was almost exclusively used. MODERN. In modern work windows are either treated simply as openings for light and air, and therefore filled with clear glass in movable sashes, usually of wood, or made internally decorative, as in the Middle Ages, by the use of stained glass. This art has been revived and extended by wholly new developments as to color and treatment, especially in the United States. and applied in both secular and religious architecture. In general the form and treatment of modern windows are made to conform to the historic style which predominates in the design, but the style is often handled with great freedom of detail. Nearly all types of Gothic and Renaissance windows may be seen in modern buildings, the Gothic being chiefly confined to ecclesiastical buildings. The use of plate glass has made possible the glazing of windows without intermediate sash-bars, with gain in light, but loss of architectural effect. Shop windows measuring ten or fifteen feet square are not uncommon, each of a single sheet of glass, but they detract greatly from the solid aspect of a building and are wholly destitute of architectural character. WINDOWPANE. A small, thin, almost translucent, variously mottled flounder (Lophosetta maculata) common along the Northeastern coast of the United States. It is a near ally of the English turbot, but is little used as food. WINDOW-SHELL. A Ceylonese 'oyster' (Placuna placenta) of the family Anomiidæ, whose valves are round, nearly flat, almost transparent, and formerly were extensively used in China and elsewhere as a substitute for window glass. In the middle of the nineteenth century their export in ship-loads was an important item of commerce in Ceylon. They abound in tiny pearls, which are saved for burning into a lime to be chewed with betel-nut by those who can afford the luxury. Compare JINGLE-SHELL. WINDPIPE. See TRACHEA. WINDSOR, win'zer. A municipal and Parliamentary borough in Berkshire, England, on London (Map: England, F 5). Of great anthe Thames, 21 miles by rail west by south of tiquity, its chief interest lies in its castle and parks. It has been a favorite residence of English monarchs. (See WINDSOR CASTLE.) Bridges connect the town with Eton and Datchet opposite on the left bank of the Thames. The town hall, built by Sir Christopher Wren in 1658, contains some royal portraits. Population, in 1901, 13,958. WINDSOB. A port and the capital of Hants County, Nova Scotia, on the Dominion and Atlantic Railroad, 45 miles northwest of Halifax (Map: Nova Scotia, E 5). It is the seat of |