BUTTON. 742 BUTTEESS. BITT'TON, Sir Thomas ( ? -1634). An Eng- lish navigator, the successor of Henry Hud- son in the search for a nortliwest passage. In 1612-13 he was frozen in and wintered on the west coast of Hudson's Bay. Tlie next summer he explored that coast, returning to England in the autumn. BUTTON QUAIL. A peoiliar quail-like bird of the genus Turiiix, family Turni<'id:r. order Hcmipodii (see Hemipode). found in the tropi<al and sub-tropical portions of the Old World. It is also called bustard quail, bush-quail, orty- gan. and hemipode. .boiit twenty species are known, (me of which — the torillo of Spain {Tuniix siilrntira) — occurs in Southern Europe. They are almost the smallest game birds known, and frequent wooded places, in small coveys, feeding on seeds, berries, and insects, and fre- quently visiting plantations. The females are more brightly colored than the males, and more forward in their manners than is usual among birds; and their extreme pugnacity is taken advantage of in India in trapping them by the help of a decoy, which they try to assail. BUTTON'S COFFEE-HOUSE. A famous place of assemblage for wits in Addison's time, situated in Russell Street, C'ovent Garden, London. BUTTONWOOD. See Piane. BUTTRESS (OF. hoiilerets, from bouter, hoter, to thrust). A structure, usually in the form of a pier, erected for the purpose of giving additional stability to a wall. It is not par- ticularly necessary, except in vaulted construc- tion, so little trace of it is found in Egyptian or Greek art. As its purpose is to "balance the outward pressure or thrust, it was not re- quired in the concrete Roman structures, where the pressure, as in a easting, was only down- ward. The use of buttresses begins in Byzan- tine architecture (see Byzantine Art), is con- tinued in Romanesque (see Romanesque .kt), and receives its complete and logical develop- ment in Gothic (see Gothic Akchitectiike), for these styles used a system of balanced thrusts. This balance was at first largely secured without buttresses, which are useful only where the pressure is concentrated at certain given points, which the buttresses are used to strengthen. For instance, in a Romanesque tunnel-vaulted church, the thrust of the high vault of the nave is continuous, and is met, say, by semi-tunnel vaults over the aisles, whose out- line is like that of the later Gothic flying but- tresses — like a ccmtinuous Hying buttress. But- tresses are of four main varieties: (1) Inter- nal; (2) external: (3) pier buttresses: (4) flying buttresses. In Saint Sophia, at Constan- tinople, two enonnous pier buttresses brace the central dome on either long side, doing what the semi-domes perform on the other sides; but the main Strain is passed down toward the ground by a skillfully arranged series of vaults over galleries, aisles, etc. In other and less bold Byzantine constructions, all the buttressing is internal. As early as the Romanesque period there is a stronger tendency to reveal structural methods on the outside. The use of exfemal buttressing in the fonii of piers became then very common, but they remained secondary in usefulness to the aisle vaulting, in resisting the pressure of the rave vaulting, and their capa- bility by increased projection to strengthen the outer walls was not thoroughly utilized. But when, as in Norman Romanesque, ribbed cross- vaulting was adopted, which concentrated the tbru,sts on the piers and on the points in the walls opposite them at the base of the vaulting compartments (see Vault), then the buttress was enabled to fulfil its real function. The Gothic framework which then developed was composed of three interacting parts, which se- cured a perfect equilibrium : ( 1 ) The cross- ribbing of the vaults: (2) the supporting piers; (3) the retaining buttresses. These Gothic but- tresses consisted of two parts — pier and tl.ving^ arch. The flying buttress was a purely Gothic invention. Suppose a five-aisled Gothic cathe- dral, with buttresses outside opposite the fall of each vaulting compartment, L.nd occupying substantially all the space between the large stained-glass windows. A heay buttress pier rises from the ground, projecting from the outer aisle wall to a point about o])posite the base of the vaulting of the nave. It is divided into three stories — the first is part of the outer aisle wall, and receives its vault thrust directly; the second is joined to the upper part of the wall of the gallery, over the inner side aisle, by a flying half arch abutting against its pier but- tress; the third is joined in the same way by a longer arch to the base of the vault of the main nave. These ll.ying arches receive the thrust and transmit it along the line of greatest re- sistance to the main pier buttress. The de- velopment of this system by Gothic architects is one of the most interesting details of the style. The earliest examples — in about 1140, at Saint Gernicr — are low and ineffective; they increase in height and heaviness as the Twelfth Century advances (Esserent, Noyon) ; and toward 120O architects Icnow just what form, position, and size are the most effective. They are then able to reduce them in bulk, the more skillfully they use thcui, and they begin to use for decorative purpose what ^^■ould seem likely to be an awk- ward blemish on the exterior of their buildings. A comparison of the buttresses of the cathedrals of Soissons, Notre Dame, Amiens, and Rheima will show how this was managed during the course of the Thirteenth Century in France. Colonnettes against the piers, pinnacles and finials as a crown, tabernacles, engaged shafts and blind arcades, gargoyles and grouped mold- ings, contributed, together with increased ele- gance of form and harmony of proportions, to- make the developed Gothic buttress a beautiful detail, as well as the most vital part of Gothic structure, by which heavy walls were rendered unnecessary. On French facades, the four great piers that divide them into tliree sections are buttresses, though other Gothic schools besides the French used the buttress ; but as they did not develop it nor thoroughly grasp its function in all its delicacy, they used it less successfully and generally. The Spanish school follows the French most closely, liut often omits the see- ondarv- pier buttress (cathedral at Burgos). Next in purity comes the Knglisli, where some- times, as at Westminster, an approach is made to French perfection. Then comes German}', at a great distance : while in Italy, with its de- fective grasp of constructive principles, the
