The encyclopaedia of the fine arts : forming a portion of the Encyclopaedia metropolitana.

Date:
1848
Catalogue details

Licence: Public Domain Mark

Credit: The encyclopaedia of the fine arts : forming a portion of the Encyclopaedia metropolitana. Source: Wellcome Collection.

    17/748 (page 241)
    Arcliitec- beams al)ove the columns, comprehending the archi- iuie. trave, frize, and cornice, was called by the general name of epistylium, but in later times, tike entablature. When an inclining roof was to be made, (see pi. i. tig. 2.) beams, called by Vitruvius cantherii, and by the present Architects, rafters, were disposed in two planes declining each way from the columen, or ridge of the roof, which ridge extended longitudinally above the middie of the area enclosed by the building: the upper extremities of the rafters were attached to this ridge, and the lower extremities rested upon the entablature vertically over the extremities of the horizontal beams in the frize. Above these rafters were placed small tim- bers, called by Vitruvius templa, by the moderns pur- lines, in horizontal positions, and parallel to the ridge of the roof; and, over them, a second tier of rafters, smaller than the former, and projecting, at their lower extremities, beyond the face of the architrave or frize on the Hanks of the building. These last rafters, in some cases, carry the tiles or other materials which cover the sloping roof; and if we may suppose them to be placed so that one rafter may be over each triglyph and metope, the projecting extremities, being imitated in the copy, will constitute what, in one of the Orders, are called mutules, whose inferior surfaces are in a plane parallel to the inclining surface of the roof in which they are placed. And though these also can only, with propriety, exist upon the two lateral fronts of any building, yet it has been, universally, the practice to depart so far from the model as to repeat them upon the front and rear faces of a complete edifice. The extremities of the pur- lines, appearing in front and rear of a building, may have suggested the idea of forming modillons in each of the inclining sides of the roof, which in some of the Orders is done ; but, in practice, a deviation is made from the character of the model by placing such mo- dillons closer together than the purlines really would be, and by forming their side faces in vertical planes instead of perpendicular to the directions of the rafters. The desire of ornamenting the inclining extremities of the roof in a manner similar to the horizontal cornice has led, in some Orders, to the employment of dentels also in those situations . as if the inclining roof had been formed by two tiers of purlines, in alternate order with the rafters, under its external covering. In the above developement of the Vitruvian hypothe- sis, it is not intended to assert that artists can, in any case, bind themselves to produce a perfect correspond- ence of all the members in the buildings they construct, with those of any model; but, merely, to exhibit a simple structure, the parts of which may have served as pro- totypes of the members we find occasionally employed in the most complex edifices. The roof of a building, when formed by two inclined planes, was, by the Ancients, called by the general name fastigium. The triangular extremity of such a roof is called a pediment, and the space included within the horizontal and inclined cornices of the pediment had, and still retains, the name of tympanum. The principal members of a finished edifice have now been compared with those of the simple hut; if we descend to the minuter parts and ornaments, we shall find that many of them may be traced to objects neces- sarily connected with the same prototype, and from which it is possible they may have been derived ; others, by their nature, are incompatible with such an origin, and, therefore, must be considered either as imitations of some natural objects, or as improvements which Part f. would easily suggest themselves when the members v,*——^ were executed in a different material. It is supposed that, originally, the trunks of trees, xhe base a! which served as posts, might have been planted imme- a column diately upon the ground ; but experience would soon show that the bottoms of the posts were liable to be destroyed by its humidity, or that the weight of the edifice would force them into it, and thus endanger the safety of the whole. An endeavour would, perhaps, be made to remedy these evils, by placing a tile or fiat stone under the bottom of the post to keep it from the ground, and, by presenting a greater surface underneath, to prevent it from sinking; from this probably originated what has been since called the plinth. The bottom of the post being liable to split by the weight above it, may be supposed to have been protected by a hoop or cord surrounding it; and, from this, some have derived the torus and other ornaments placed above the plinth, which, with the latter, form the base of the column. Now it might happen that the tops of the posts were iyie capitaL not exactly situated in a horizontal plane, from the in- equality of the ground, or of the lengths of the posts ; and, in such a case, the architrave which was placed upon them, might not touch every one. In order to remedy this, it maybe supposed that flat tiles, or stones, would be placed above the posts, having their thick- nesses so regulated that the under surface of the archi- trave, when in a horizontal position, might rest upon each. If this opinion is well founded, one of these tiles may be represented by the abacus of the column in the finished building ; and ropes surrounding the tops of the posts, like those in the base, might have been the origin of the echinus, the astragal, and some other of the ornaments, which constitute what is now called the capital of the column. The column may, therefore, be considered as tormed of three parts or members, viz. the base, the body or shaft, and the capital. It must be owned, however, that bases and capitals are not, universally, the accompaniments of columns; in some edifices, we find columns without bases, in others, we find them without capitals, and there are some columns without either bases or capitals; neither do all capitals of columns resemble ropes or rings, on the contrary we find, in this member, a very great di- versity of form, and the talents of artists have been particularly exerted to give it all the beauty of which it is susceptible. Some columns have their upper extremities adorned with spiral curves, or volutes, projecting beyond the surface of the shaft, and the opinions concerning the origin of these ornaments have been various. Vitru- vius asserts that they are imitations of the curls of hair about a woman’s head; but later inquirers think they were derived from the curling leaves of plants, or from the horns of animals slain in sacrifice ; with which a capricious taste might, on festival days, have decorated the columns of a Temple. It is difficult to say which of these ideas is the most just, and, perhaps, none of them deserve much consideration. In other columns we find the capitals consist of two or more rows of leaves surrounding the shaft, at its upper extremity, so as to resemble very much the foliage of a plant growing round the side of a cylindri- cal or bell-shaped vessel. And, according to Vitruvius, it was from the casual observation of such an object, near Corinth, that the idea was first taken. This account