Various arrangements of line, form, and color produce an effect other than the real. Reflection in a mirror or quiet pool of water is an illusion to the visual senses. A mirage in which an oasis and trees and the likeness of water appear is an optical illusion. In nature protective coloration of animals produces the effect of illusion. When man-made, this effect is called camouflage. The zebra has a strikingly colored body that in the brush or grass of his natural habitat gives the effect of the strong sunlight falling through the grass. Snakes have mottled colorings, and so their bodies appear to blend with the rocks and vegetation. Many animals have light-colored bellies which eliminate the shadow and thus fool their natural enemies. Fish become almost invisible under certain conditions in the water. In winter, certain birds and fur-bearing animals change color and thus are able to “melt” into the background.
The French phrase trompe-l’ oeil, or “fool the eye,” describes a device frequently employed by interior decorators. “Fooling the eye” may be effected in many ways, among them the placing of mirrors to reflect out-of –door scenes and to make a room appear larger; the use of a color on walls or ceiling to add apparent height or width to a room; the use of simulated doors or windows to balance a displeasing feature; and the use of properly selected and hung curtains to enhance the appearance of a room. The use of yellow, orange, or red creates the illusion of sunlight in a room having only north light. Paintings which have a double image are other examples of this same trick of prompe-l oeil.
At the Metropolitan Museum of Art in New York a small unusual room called the Gubbio room was installed. This paneled room had been constructed for an Italian gentleman to amuse his friends. In it, the art of illusion was employed with striking success. Delicately colored pieces of wood were inlaid to produce the effect of open cupboards with books, musical instruments, and even a bird cage, inside. The entire interior was covered with this deceptive inlay.
In apparel, this effect of illusion is demonstrated in many ways. Comfortable but must also enhance the appearance of the wearer, most well-designed clothing embodies some elements of illusion. By emphasizing the dominant lines in a costume in one direction or another, for example, the figure may be made to appear larger, taller, or smaller, as desired. Padded shoulders in dresses, suits, and coats, if combined with a fitted hipline and waist, make the hips appear narrower and the shoulders broader. High revers, lapels, or neckline ornaments add apparent height.
By association, various dominant lines suggest various effects. The weeping willow is a symbol of sorrow, and so a person with drooping lines around the mouth, disheveled hair, and stooped shoulders also gives this same sorrowful effect. “Thumbs up,” a slogan adopted to evidence courage during the war, suggests the effect of upswept lines. There is a spiritual quality in the upswept vertical line. It suggests growth, as all plants grow upward. Trees, church spires, and columns inspire a feeling of reverence. This vertical line in clothing is seen in hats with upstanding feathers which add apparent height; center front closures on dresses, suits, and coats with contrasting color buttons or fasteners; narrow lapels and ties; hats with pointed crowns; lengthwise-striped fabric; slash-pockets; and the vertical use of tucks, buttons, ruffles, bandings, or other details.
Horizontal lines add apparent width to a room or a person, for the eye tends to follow a dominant line. A straight, wide-brimmed hat, therefore, tends to make the wearer appear broader and shorter. Jackets of colors which contrast with trousers or skirts also have this effect. Yokes, pockets, contrasting color belts, embroidery and other decoration, or structural horizontal lines add apparent width to the figure. Jackets and coats, fingertip or shorter than the dress, make a tall person appear shorter.
Slanting and gracefully curved lines are most frequently employed in apparel. The slanting line is seen in the surplice neckline, the lapel and closure of a man’s suit, the silhouette of a circular skirt, and the bias cut of striped fabric for dresses and men’s ties. An evening dress made with a full skirt and a tight waist-and hipline makes the wearer appear taller than does a tight dress with a narrow skirt.