Another Working Steamboat.—This time our boat will merit its name—for we shall have a boiler, and generate a supply of steam.
If you look at Fig. 91 you will get a good idea of the construction of this model, and realise how simple it really is. The boiler is provided by a medium-sized flat oblong tin, with the lid soldered down so that it is steam tight. For the purpose of putting water into the boiler when necessary, a hole is bored in the lid, and a cork fitted tightly.
Fig. 91.
In one end of the boiler, and towards the top, you must make a pin hole. When the water boils well, the steam is expelled through this tiny hole with considerable force; and to this is due the motion of the craft.
The remainder of the fitting up is soon done. A flat hull similar to that described on page 70 is prepared, and four flat-headed nails driven in, so that the four corners of the boiler can each stand on a nail head. The rudder is cut from an old piece of tin, and pressed into a knife-cut made in the centre of the stern of the hull.
The boiler is placed into position with the steam hole facing the stern, and lighted candle ends are then placed underneath the boiler—as many as possible; for the more the candles the greater the heat, and consequently the greater the force of steam. It will help matters along considerably if the boiler is first of all filled with hot water, instead of cold; but be careful not to scald yourself in doing this.
When steam is up, the boat should travel along at quite a comfortable pace.