BLACKBOARD SKETCHING

PLATE 20

The strokes on plate 20 are so well defined that it hardly seems necessary to describe them. For a short piece of chalk is used, the side of the chalk giving the width of the line. At 2 the stroke is similar, the accent being at one end of the chalk. At 3 the stroke is slightly curving, the chalk being placed vertically, and the accent being upon the upper end of the chalk. No. 4 is drawn by placing the chalk vertically upon the board, drawing it downward very quickly and twisting it to the horizontal position. Apply these strokes in sketching the lobster. First use stroke 3, then touches like 2; afterward strokes 1 and 4 for details.

No. 5 indicates the strokes first used in sketching the shells. In drawing the outside of the nautilus, use a long piece of chalk and with a curving stroke accented with the end, form the out­line. With strokes similar to those at 2, sketch the light streaks in the shell, and add dark details with charcoal. Use the tip of the finger in softening the tones here and there.

In drawing the section, sketch first the spiral curve, then the blended strokes connecting the outer with the inner curves of the spiral, and add charcoal for shadows.

The oyster shell is drawn by the use of the lower stroke at No. 5. Make the stroke, accenting a little at the left end of the chalk; then reverse the stroke, accenting with the right end, and add details with chalk and charcoal.