Fig. 14.
The best arrangement is depicted in Fig. 15, which has a pilot-tube burner as well as the two main tips. On turning the key, gas is admitted to both main and pilot burners, but the electrode in breaking contact only ignites the gas at pilot burner, which, in its turn, acts as a lighter for the main burner. Turning the main burner out, the pilot light can be left burning if desired, giving a small light, it being not feasible to turn down the main burner owing to the before-mentioned carbonization.
Fig. 15.
The orifice of an acetylene burner is much smaller than that of a coal gas burner, the former burning about one-half foot per hour, against six or seven feet of the latter.
Burners for Gasolene.
The flame from this gas is hotter than that of coal gas, and deposits so much more carbon that a slight modification is necessary in the construction of burners for it. The details can be readily seen on observation of a burner, being simply in the adjustment of the contacts and their operation. It is better, however, to use a larger coil and a stronger battery for gasolene gas lighting than would be needed for coal gas—say, 6 cells of Samson, or large-size New Standard dry battery and a 10-inch coil having about 4 pounds or more of wire on it.