The sides and ends of the car body are made of sheet-iron or tin. Figure 269 shows the pattern and dimensions for these parts. They may be made from one piece of metal eighteen and one-half inches long and three and three-quarters inches wide. The doors and windows are cut out with a pair of tin-snips. The small projections along the top are bent down at right angles and the roof is fastened to them. The dotted lines indicate the places for bending these projections and also the sides and ends of the car. [Illustration: Fig. 270.—The Roof of the Car.] The roof is made in two pieces. It also is sheet-iron or tin. The roof proper is eight inches long and four inches wide. It has a hole five and one-half inches long and one and three-quarters inches wide cut in the center. A number of small projections are left and bent upward to support the deck and to form imitation ventilators. The deck is six inches long and two and one-quarter inches in width. It is placed in position on the roof and fastened by soldering. The roof is fastened to the sides and ends of the car by soldering. It must be bent slightly to conform with the curve at the top of the front and the rear of the car. [Illustration: Fig. 271.—The Completed Car.] The car when completed will appear as in Figure 271. The track is made of smooth spring steel, one-half inch wide and either No. 20 or No. 22 gauge in thickness. [Illustration: Fig. 272.–Details of a Wooden Tie.] The wooden ties are three and one-half inches long, three-quarters of an inch wide and three-eighths of an inch thick. Each tie has two saw-cuts, exactly two inches apart across the top face. This part of the work is best performed in a miter-box so that the cuts will be perfectly square across the ties. A saw should be used which will make a cut of such a size that the steel track will fit tightly into it. The distance between the two rails of the track, or the "gauge," as it is called, is two inches. [Illustration: Fig. 273.–Arrangement of Track.] The track is assembled as in Figure 273. The spring steel is forced into the saw-cuts in the ties by tapping with a light wooden mallet. The ties should be spaced along the track about three inches apart. The work of laying the track must be very carefully done so that the car wheels will not bind at any spot. Curves should not be too sharp, or the car will not pass around. The track may be laid out in a number of different shapes, some of which are shown in Figure 274. [Illustration: Fig. 274.—Three Different Patterns for laying out the Track.] A circle is the easiest form of track to make. In laying out a circle or any sort of curved track, the outside rail must necessarily be made longer than the inside one. The oval shape is a very good form to give the track in a great many cases, especially where it is desirable for the car to have a longer path than that afforded by a circle. [Illustration: Fig. 275.—Details of the Base of the Cross-over.]