Star-shaped openings were now cut in this cambric, as shown by the stars in the central portion of Fig. 1.
The second circle was placed about six inches back of this (see Fig. 3, A 1 and A 2). It was held in position by braces F F, Fig. 3. These two circles formed a track on which the earth slowly revolved. Another circle was next formed, similar to the first one, except that this had four spokes, I I I and J, Fig. 2. The spoke marked J was long enough to reach the center of the globe and connect to an axle, as seen in Fig. 3. This circle was also covered with black cambric, and irregular holes cut in it (H H H, Fig. 2), over which pieces of red tissue paper were pasted. These are represented by the irregular patches in Fig. 2. This rear disk was fastened to a pivot (Fig. 3) and placed three inches back of the front disk in which the stars and sun were cut. As it slowly revolved it carried the globe around with it, and the irregular tissue paper opening coming opposite each star caused the stars to twinkle like those in the corners.
The earth was constructed as follows: Two bushel baskets were procured, the handles cut off, and a brace nailed across the center of each. Holes were bored in the middle of these braces, and an axle inserted (B, Fig. 4) and made fast to the bottom of the basket. Then the spoke J, Fig. 4, which has a hole in the end, is slipped over the axle and the other basket placed in position and fastened opposite the first. The baskets were left far enough apart to allow them to revolve. In Fig. 4, A A, are the baskets, B is the axle, c c c c braces, J the spoke, corresponding with J in Figs. 2 and 3.
The profile drawing in Fig. 3 will enable you to see the mechanism at a glance. A1 and A2 are the circles on which the globe representing the earth revolves; B is the disk with the long spoke, J, placed between these two circles; C is the pivot which causes disk B to revolve. D D are the braces holding disk B in position. F F and I I are the braces holding A1 and A2 in position; G is the pulley on pivot C that run the different parts; K is the main belt leading from the basement; L L L are belts running to pivots H H H. All framework liable to show should be made black; also have the cords you use for belts black.
REVOLVING CYLINDER.
This is a simple but very effective mechanical contrivance, and may be constructed by any amateur:
Make three circular pieces from one-inch planed boards, A A A. Through the exact centers of these run a rod, EE. Nail two-inch strips, c c c, placed a little distance apart, over the discs, one of which is placed at either end, and the third in the center. This forms the barrel, AAA, with the rod, EE, as pivot. This pivot rests on crotches, DD, allowing the barrel to revolve when the motive power below (at G) causes the fly-wheel, which is securely fastened to E, to turn by means of the circular band, B. The crotches, DD, should be high enough to bring the barrel to the center and middle of the window.
THE READING CYLINDER.
Cover the barrel with cloth—a dark material is best—and upon this pin or tack the articles to be displayed. Almost any articles, not too large, may be shown, and they should be so arranged as to present variety as the wheel revolves. Suspend a screen in your window that will cover the mechanical apparatus, only allowing the front section of the barrel to show. Thus, as the barrel slowly revolves, a panorama of merchandise is shown the observer, and the constant change will undoubtedly attract much attention. You may letter the screen in any manner that suits your fancy, and this arrangement will not prevent your placing other goods in the window before your screen, as the revolving barrel will be high enough not to interfere with anything shown on the window floor.