22. It cannot be too strongly emphasized that the student must teach himself to regard the subject he is depicting, as a whole, and to put down at once lines that suggest the outline of the whole. This he will find contrary to his inclination, which with the beginner is always to work out carefully one part of the draw ing before suggesting the whole.
There are two objections to this_; in the first place, much time having been spent on one part, it is almost inevitable that the addi tion of other portions reveals faults in the completed part, and un necessary time is consumed in correcting. The second objection is that a drawing made piecemeal is sure to have a disjointed look, oven if the details are fairly accurate in their relative proportions.
The idea of unity is lost and some one detail is apt to assume un due importance, instead of all details being subordinated to the general effect of the whole. It is always most important to state the general truths about the subject rather than small particular truths, which impair the general statement. This applies particu larly to small variations in the outline which should be omitted until the big general direction or shape has been established.
23. Where an outline drawing is desired, after the correct lines have been found, they should be made stronger than the others and then all trial lines erased. In doing this the eraser will usually remove much of the sharpness of the correct lines so that only a faint indication of the desired result remains. These should be strengthened again with A softer pencil and each line produced, as far as possible, directly with one touch ; in the case of curves and very long lines, breaking the line and beginning a new one as near as possible to the end of the previous line, but taking care that the linei do not lap.
As soon as the student has acquired some proficiency in draw. ing the single figures made from the tablets, groups of two or three objects should be attempted. Combinations of books or boxes with simple shapes, or vases, tumblers, bowls and bottles will illus trate most of the principles involved in freehand perspective. Outline sketches may be made on the slate first and tested in the usual way, and afterward the same group may be drawn larger on paper. The chief difficulty in drawing a group is to obtain the rela. tite proportions of the different objects. There is the same objec tion to completing one object and then another as there is to drawing a single object in parts. The whole group must be sug gested at once. This can best be done by what is called blocking in, by lines which pass only through the principal points of the group. The block drawing gives hardly more than the relative height and width of the entire group and the general direction of its most important lines. But if these are correct, the subdivision of the area within into correct proportions is not difficult. The longer and more important lines of the parts are indicated and short lines and details lost. • .
24. 'Testing Drawings by Measurement. In drawings which are not made on the slate the following method of testing propor.
tioas is usual. With the arm stretched forward to its greatest length, hold the pencil upright so that its unsharpened end is at the top. Move it until this end coincides with the uppermost point of the object. Holding it fixed and resting the thumb against the pencil, move the thumb up and down until the thumb nail marks the lowest point of the object. The distance measured off on the pencil represents the upright dimension. Holding the pencil at exactly the same distance from the eye, turn it until it is horizon tal and the end of the pencil covers the extreme left point of the object. Should the height and width be equal, the thumb nail would cover the extreme right edge of the object. If the width is greater than the height, use the height as a unit of measurement and discover the number of times it is contained in the width. Always use the shorter dimension as the unit of measurement. The accuracy of the test demands that the pencil should be at ex actly the same distance from the eye while comparing the width and height. In order to insure this, the arm most not be bent at the elbow and must be stretched as far as possible without turning the body, which must not move during the operation. The dis tance from the eye to the object must not change during the test, and the position of the eye and body is first fixed by leaning the shoulders firmly against the back of the chair and keeping .them in that position while the test is taking place. It is equally impor tant in both the upright and horizontal measurement that the pen cil be held exactly at right angles to the direction in which the object is seen; i.e., at right angles to an imaginary line from the eye to the center of the object. In either position the two ends of the pencil will be equally distant from the eye. The test should be made several times in order to insure accuracy, as there is sure to be some slight variation in the distances each time. Avoid tak ing measurements of minor dimensions, as the shorter the distances measured the more inaccurate the test becomes. At the best meas urements obtained in this way are only approximately correct, and too much care cannot be taken in order to render the test of use. Applied carelessly, the test is not only valueless, but thoroughly misleading. When there is any great conflict between the appear ance of the object and the drawing after it has been corrected by the test, it is often safe to assume some mistake in applying the test and to trust the eye. In such a case the test may be tested by the use of the slate. A few lines and points will be sufficient to indicate the width and height on the slate, and the relative propor tions can then be calculated.