THOUGH a large percentage of all perspectives and renderings made for architectural purposes show exteriors of buildings, the draftsman is, nevertheless, sometimes called upon to make drawings of interiors, including such accessories as furniture and draperies, and, as interiors offer certain problems not usually encountered in exterior work, special practice and study are necessary to insure their satisfactory solution. Then, too, there are some draftsmen and designers, particularly those employed by decorators, or in furniture or upholstery houses, who devote the greater portion of their time to rendering interior subjects, and these men. even more than those doing the usual form of architectural work, need a knowledge of how interiors actually appear and how this appearance can be best represented.
A lengthy discussion of this interesting subject seems hardly necessary, for many of the suggestions already offered in previous chapters relate to interior as well as to exterior work, and, therefore, as some special comments have also been made which refer to interiors only, it is our present purpose merely to add a few ideas, bearing especially on methods of representing some of the many objects and materials which do not appear in exteriors, such as the furniture and draperies mentioned above. Before doing so, however, it will perhaps be well to first call attention to a few of the essential differences in the appearance of interiors and exteriors, for a comparison of these differences, and of their effect on the manner of indication should prove of value to the student.
First of all, interiors are considered by many artists to be more difficult to draw than exteriors, and for a number of reasons. To begin with, the actual mechanical process of laying out an interior, preparatory to the work in rendering, is usually more laborious than for an exterior. Exteriors are, to be sure, often far from simple, but when doing an office building or a hotel or some structure of similar general form, the mass of the whole is seldom complicated, so it is usually easy, once the main construction lines are instrumentally laid out, to project the various measurements of the windows and the like along the wall surfaces to the desired position. Interiors, however, though often as simple in mass, are only begun when the architectural shell of ceiling and floor and walls (with their accompanying doors and windows) is completed, for there remain such details as furniture and lighting fixtures, and these require considerable time, for it is. as a rule, rather a lengthy process to accurately obtain all of the different measurements in perspective, as many of these objects stand away from the walls, which adds to the difficulty of projection; and once the correct placing and general dimensions are obtained, it is frequently the case that the objects themselves are so irregular in form as to necessitate considerable labor, for often many curved or slanted lines are required; - in fact, such pieces as rocking chairs sometimes consist entirely of curved lines and lines sloping at various angles. Then, too, it is not uncommon to find furniture so turned that nearly every piece requires vanishing points of its own. It is, therefore, mainly because of such accessories that the mechanical layout of the typical interior proves laborious to make, though there are certain types of buildings where the block form itself is difficult. One of the hardest kinds of interiors to draw accurately is the theatre, where the bowled floor, the disposition of the seats in curved rows with radiating aisles, the rounded and sloping balconies, the tiers of boxes, the proscenium arch and the vaulted or domed ceiling, all offer labor enough to tax the patience of the most persevering.
In addition to this difficulty of instrumental construction, the draftsman of interiors is some-limes handicapped a bit by his inability to introduce accessories just where he wishes to have them for the purpose of obtaining the best composition. In drawing exteriors the artist can often make an otherwise ordinary composition interesting by arranging his trees and vines and clouds and automobiles, - in fact, all such accessories, - about where he wishes, and many of these can be made, also, of almost any desirable size and shape. Interiors sometimes permit the use of potted plants and vases of leaves or flowers to serve a like purpose, and of course in conservatories we find much of this sort of thing, but on the whole there is less opportunity for such freedom of arrangement, though the furniture and pictures and hangings do offer a similar means of relieving the bareness of the architectural background, so that this of course offsets to some extent the handicap just mentioned.
Another difference in appearance between interiors and exteriors is found in the effect of the light and shade, for in exteriors the sun usually affords a single direct means of illumination, so that the shadows can be laid out by an accurate mechanical method, if one knows the science of doing so, and the division between the light and the dark is generally clearly marked. Interiors, however, are usually far more complex in their lighting, the rays of light coming frequently from several sources, thereby causing complicated values, the shadows often falling in a number of directions at the same time, and the tones of these various shadows differing greatly, some being light and others dark, with certain edges sharply defined and with others indistinct. A chair leg, for example, often casts several shadows on the floor at once and a lighting fixture as many more on the wall or ceiling. This complication is further augmented by the numerous reflections, concerning which we will say more in a moment, but notwithstanding all this, the mere fact that such a complex condition does exist, though often very confusing to the beginner, frequently works to the advantage of the more experienced man, for, as we are accustomed to this complexity of tone, the skilled artist is able to arrange his values almost as he chooses and we are unaware that any liberties have been taken so long as the natural effect has not been sacrificed.