and as soon as it is full it runs over and the tap it is closed. A match is then applied to a hole in the side of the box g, and the petrol in the small cup lighted; it burns under a tube of Г shape filled with copper borings and heats it and them. This Г has a tap c to it, so that petrol can be injected through it, and when it is heated the petrol, as it percolates through the hot copper borings, is vaporised. As soon as the petrol in the cup is nearly burnt out, the tap c is turned, which admits petrol from the pipe f into the Г tube burner above the cup. The flame of the petrol left in the cup lights this 'pilot burner,' and it projects its flame on to the vaporising tube across the fire-box, which supplies petrol to the main burner. When this is believed to be heated sufficiently to vaporise the petrol it can be tested by turning the tap d,
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Fig. 3.—The Western Apparatus lor Starting the Burner
when, if the fuel is not vaporised, liquid will issue from the tap d1, and a minute or two longer must elapse before the main burner can be started. As soon as gas is found to issue from d1, e is slowly opened, and this admits the vapour into the main burner. It issues into the fire-box, and is ignited by the pilot light. As the heat increases the petrol tube across the fire-box becomes sufficiently hot to vaporise the full supply of fuel, and steam is raised. The pilot light burns continuously, so that when running down-hill or when leaving the car, the main burner can be turned right out; as the pilot light is always burning the burner can be relighted instantly as soon as petrol is turned on again. In the Locomobile the initial heat is usually obtained by a U tube, which is separated from the car, and has to be heated in a fire or gas flame. It is then put into the fire-box and
