REPRESENTATION OF SURFACES WITH HINTS ON THE DELINEATION OF DISTANCES. LAND SLOPING FROM THE OBSERVER. LIGHT AND SHADE.
The most convenient length of crayon to use, is a piece about an inch and a half or two inches long, yet we may often profitably use the whole side or length of the crayon. If we wish to represent broad surfaces, we will naturally use the side of the crayon, as a child does. To show narrower widths of surface press more upon the end of the crayon, also use a long edge to represent the edges or the meeting of surface planes. This manner of using the crayon seems the most natural for the purpose, and it certainly economizes time.
Line represents direction. When applied to surface we understand it to indicate horizontal, vertical, oblique, and curved surface directions. Try it and see if it is not true that lines in one direction never indicate any other direction; the vertical can never be mistaken for the horizontal, or the reverse. For the representation of a level plain, make simple strokes in the horizontal direction with the side of the crayon, and to represent a vertical surface as a cliff, make a stroke in the vertical direction with the same broad side of the crayon. Oblique surfaces, as slopes, are to be drawn with oblique strokes, and curved surfaces like rounded hills, represented by continuous upward and downward strokes. (See [Fig. 1].) In the delineation of mountain masses, that are high with abrupt declivities as well as gradual slopes, we use the side of the crayon with an oblique stroke as in [Fig. 2]. We see then that right direction of lines of themselves illustrate surface planes, elevations or depressions.
1 2 3 4 5
Detail of structure, however, cannot be well brought out except by effects of light and shade. Choose from which direction your map or sketch is to be lighted, and keep it always in mind while drawing. Study the effects of light and shade everywhere. Note the length of shadows at different times of the day, and their relation to the position of the sun.
To represent an unbroken sweep of land or water, as of a plain or lake, draw a broad unbroken line for the distance, as all detail of surface forms seems to merge into one horizontal mass; nearer to us, we perceive more detail of landscape or broken land surface, which we may represent with broken lines. This is the most simple representation of level distance. (Note [Fig. 3].)
In [Fig. 4], or the representation of a plateau (upraised mass of land), there are horizontal, vertical, and oblique surfaces combined. The detail of structure in the foreground is represented with some definiteness of line, while the mountain slopes are quite indefinite. Notice that the oblique and vertical lines are shorter in the distance than in the foreground, and that the land seems to rise as it recedes from us. Look out of doors and see if it is not so. Notice rows of trees, houses, or telegraph poles, in their relative height, also in their relation to the ground on which they stand.