Page:American Journal of Sociology Volume 3.djvu/612

 59$ THE A. M ERIC A \ JOURNAL OF SOCIOLOGY

li'ish ; the iiioU)!- nerves send sensations to the brain, but these are not received as definite lasting impressions, so we must be particular in class instruction to give but a single impression at a time, introducing tools which call tor a tree- muscular move- ment, emploving the mass movement before going to the com- binations. Work is upon a project which involves few tools and a single impression, so that the mental concept can assimilate the desired truth, use it, tabulate it, and file it for future use.

In model No. i (p. ;g;j is shown at top left a block of wood, also a finished piece called a wedge. At the top right is the free- hand sketch, in the lower view is the mechanical drawing. The pupil makes the free-hand drawing from a perfect model, then with paper, rule, pencil, and "T" square draws the mechanical representation. A thorough drill is made upon the twelve lines which indicate the size and form of the model ; then a block is supplied from which the tool performances begin. This tool is the knife. In operation the pupil stands firmly, with one foot a little in advance of the other, the left elbow lightly touching the side ; the left hand holding the block securely, the right hand holding the knife, and a swinging motion beginning from the elbow joint, a cut on the block is made; this is a contracted movement of the lower biceps muscles of the right arm.

These muscular expressions have habituated the motor nerves to send definite messages; the brain has received them. Simple arithmetic has been employed and something produced. The result of these actions is mental quickening through tool performance

In the preceding models before No. 8 (p. 597) we have, with two exceptions, used the single impression idea, with such change in models as would employ different muscles and motor nerves. Model No. S is one of the three in the course wherein special com- binations of muscular activities are employed, and motor nerves are employed in sending to the brain ideas in rapid succession.

The operations are as follows : First, the free-hand sketch from an accurate model, then the mechanical drawing; this accepted, the tool performances begin. The finished project is composed of six pieces ; stock for these is supplied in rough.