[Illustration: Fig. 19.] [Illustration: Fig. 21.] [Illustration: Fig. 22.] By this time the framework will be quite dry, no doubt, so you can, after cleaning and polishing the boiler, attach it to the frame by a screw or solder at the forward end, and the steam-pipe N can be screwed on to the projecting piece of tube left at F, while you also screw a short length of pipe into the steam box of engine through a hole in the bed plate. Then bend it up to the steam tap, and solder them carefully in position; this will hold the after end of the boiler firm. Go over every soldered joint to see if any small hole is left, and resolder where necessary, as a hole in the boiler not larger than a pin's point would prevent you from getting any pressure of steam in the boiler, as the water would all blow out. Now lacquer or paint your boiler, and while it is drying turn your attention to the lamp, which we picture in Fig. 18. THE LAMP. The lamp is simply an oblong tin box, about 5 inches long by 1-1/4 inches wide and three-quarters of an inch deep. To make it cut a piece of tin 4-1/2 by 5 inches and bend it to shape. Then solder the two edges together and cut two ends to fit; push them in and solder in place. Now cut three pieces of brass quarter-inch tubing into three-quarter inch lengths; drilling holes in top of lamp, insert them, allowing a quarter of an inch to project, as at A, Fig. 17. Then solder them on four pieces of bent wire--C, C, C, C, Fig. 18--by which to hang the lamp by means of two wire pins run through them and small holes drilled in the sides of projecting piece C, Fig. 10. The screw filler B, Fig. 18, will have to be soldered in, also, and when complete the tubes A may be filled with cotton wick and the lamp about three-parts full of a methylated alcohol, which will give a clear, smokeless flame. Now you can start your locomotive by filling the boiler about three parts full of hot water, and then hooking the lamp underneath; you will soon get up a good pressure of steam. See that the taps are all turned off, and if there is no leakage from careless workmanship, you will find on turning the steam tap on, that the locomotive will run beautifully and will travel at great speed either on a smooth oil-cloth or a board floor. On rails it would run quicker still, but for this engine, if you make a small tender of the shape shown in Fig. 19, and fasten it at any angle by the set-screw on the foot-plate of the engine shown at N, Fig. 2, the model will run in any sized circle you may wish without rails, according to the angle you fix the tender to the engine. Wooden cars you can make if you wish, but each one added will reduce the speed of the engine, of course.