Inasmuch as the movements in question are often very slight, somewhat delicate apparatus is required to secure their record; the apparatus must in a measure exaggerate the tendency to motion though without altering its nature. The form of apparatus which I devised for this study, and which may be appropriately called an automatograph, is illustrated in the accompanying figure (p. 310). It consists of a wooden frame, enclosing a heavy piece of plate glass (fifteen inches square), and mounted upon three legs which are provided with screw adjustments for bringing the plate into a perfect level. Upon the plate of glass are placed in the form of a triangle three well turned and polished steel or brass balls; and upon the balls rests a thin crystal-plate glass set in a light wooden frame. The finger-tips of one hand rest upon the upper plate in the position indicated. When all is properly adjusted and glass and balls are rubbed smooth with oil, it is quite impossible to hold the apparatus perfectly still for more than a few seconds; the slightest unsteadiness or movement of the hand at once sets the plate rolling with an irregular motion. If one closes the eyes and fixes the attention upon a definite mental image or train of thought, it is easy to form the conviction that the plate remains quiet, but the record proves that this is not the case. The other parts of the apparatus are designed to give a record of the movements of the plate. Fastened to the light frame containing the upper glass plate is a slender rod some ten inches long, bearing at its end a cork; and piercing the cork is a small glass tube within which a snugly fitting glass rod has room to move. The rod is drawn to a smooth, round point; and when in position rests upon a piece of glazed paper that has been blackened over a flame and then smoothly stretched over a small glass plate. The point of the rod thus records easily and accurately every movement of the hand that is imparted to the upper plate, and by the manner of its adjustment accommodates itself to all irregularities of movement or recording surface. This recording device is shown in greater detail in the illustration, and was used to good advantage as a simple automatograph in independence of the balls and plates. In that case the recording part is held in the hand as though it were a pencil, but in a vertical position, and the record plate may be placed upon a table; or for special purposes the plate may be held in the other hand or fastened to the top of one's head. When not otherwise stated, the records here reproduced were obtained by use of the automatograph. Some of the records are noted as having been secured with the simpler device just described.