Page:Encyclopædia Britannica, first edition - Volume I, A-B.pdf/421

 ARCHITECTURE. 355 ed, one above another, the laws of folidity require, the caufe, when they are nearer each other than three feet, ftrongeft fhould be placed lowermoft. Hence the Tufcan there is hardly room for a bulky perfon to pafs between muft fupport the Doric, the Doric the Ionic, the Ionic them. the Compofite or Corinthian, and the Compofite the CoOF ARCHES. rinthian. This rule, however, is not always ftri<ftly adhered to. Arches are not lb magnificent as colonnades; but Moft-authors place the Compofite above the Corinthian. they are more folid, and Ids expenfive. They are pro- There are likewife examples where the fame order is per for triumphal entrances, gates of cities, of palaces, of repeated, as in the theatre of Statilius Taurus, and the gardens, and of parks; and, in general, for all openings Colifeum ; and others, where an intermediate order is that require an extraordinary breadth. omitted, and the Ionic placed on the Tufcan, or the CoThere are various manners of adorning arches. Some- rinthian on the Doric. But none of thefe piaftices ought times their piers are rufticated; fometimes they are adorn- to be imitated. ed with pilafters, termini, or caryatides; and fometimes they are made fufficiently broad to admit niches, or win- In placing columns above one another, the axis of all dows. The circular part of the arch is either furround- the columns ought to correfpond, or be in the fame percd with ruftic key-ftones, or with an archivolt enriched pendicular line, at leaft in front. with mouldings; which, in the middle, is fometimes in- With regard to the proportions of columns placed aterrupted by a confole, a malk, ferving at the fame time bove each other, Scamozzi’s rule, That the lower diaas a key to the arch, and as a fupport to the architrave meter of the fuperior column fhould conftantly be equal of the order. The archivolt is fometimes fupported by to the upper diameter of the inferior one, is univerfally an import, at the head of the pier; and, at others, by efteemed the beft, and gives all the columns the appearcolumns placed on each fide of it, with a regular enta- ance ©f one long tapering tree, cut into feveral pieces. blature, dr architrave cornice. There are likewife in- According to this rule, the Doric column will be to the rtances of arcades without piers, the arches being turned Tufcan, as 13-f to 14 ; the Ionic to the Doric, as 15 on fingle columns, as in the temple of Faunus at Rome, to 16; the Compofite or Corinthian to the Ionic, as eirc. This pra&ice, however, ought to be feldom imi- i6y to 18; and the Corinthian to the Compofite, as tated, as it is neither folid nor handfome. l6y to 20. When arches are large, the key-ftone ftiould never be In Britain there are few examples of more than two omitted, but cut in the form of a confole, and carried ftories of columns in the fame alpe<ft: And,, though in clofe under the foffit of the architrave, which, on account Italy, and other parts of Europe, we frequently meet ef its extraordinary length, requires a fupport in the with three, and fometimes more; yet it is a pradice by middle. The imports of arches fhould never be omitted; no means to be imitated; for there is no poffibility of aat leaft, if they be, a platform ought to fupply their voiding many ftriking inconfiftencies, or of preferving the place. If columns are employed without pedertals in ar- charader of each order in its intercolumnial decorations.. cades, they fhould always be railed on a plinth. In all arches, the circular part ought not to fpring immediately OF BASEMENTS AND ATTICS. from the import, but take its rife at fuch a diftance above it, as is necefiary in order to have the whole curve feen In stead, of employing feveral orders one above the other in a compofition, the ground-floor is fometimes at the proper point of view. The void or aperture of arches fhould never be higher* made in the form of a bafement, on which the order nor much lower, than double their breadth ; the breadth that decorates: the principal, ftory is placed. The proof the pier fhould feldom: exceed two thirds, nor be lefs portion of thefe bafementa is not fixed, but depends onthan one third, of the breadth of the arch ; and the an- the nature of the rooms on the ground-floor. In the gular pier ought to be broader than the others,, by one palace of the. Porti in Vicenza, the height of the bafehalf, one third, or one fourth; the import fhould not ment is equal to. that of the order. In fome buildings, be more than one feventh, nor lefs than one ninth of its height exceeds two thirds of that of the order • the aperture; and the archivolt muft not be more than and in others only half the height of the order. It is one eighth, nor lefs than one tenth of it. The breadth not,, however, advifeable to. make the bafement; higher of the confole muft, at the bottom, be equal to that of than the order it fopports; neither fbould it be lower the archivolt; and its fides muft be drawn from the cen- than one. half of the order. tre of the arch: The length of it muft not be lefs than The ufual method of decorating bafements is with one and a half of its fmalleft breadth, nor more than ruftics of different kinds. The beft, where neatnefs and double. The thicknefs of the pier depends on the breadth finilhing is aimed at, are fuch as have a fmooth furface. of the portico; for it muft be ftrong enough to refift the Their height, including the joint, .fhould never be lefs, preffure df its vault. But, with regard to the beauty nor much more, than half a module of the order placed of the building, it fhould not be lefs than one quarter oF on; the bafement. Their figure, may be from a fquare to the breadth of the arch, nor more than one third. Thefe a fefquialtera.; and their joints may be either fquare or are the general dimenfions of arches. chamfered. The fquare ones fhould not be broader than one eighth of the height of the ruftic, .nor narrower than OF ORDERS ABOVE ORDERS. one tenth ; and their depth muft be equal to their breadth; Wh en, in a building, two or more orders are employ* thofe that are chamfered, muft form a redangle ;. and the breadth: