CHANNEL DEMARCATION.
267
In the Matthews burner (fig. 232), vaporisation is eflected in a brass
tube coiled above the mantle and inclosed in a metal hood.
In the Luchaire burner (fig. 233), the vaporising tube takes the form
of the letter U inverted, and arches the mantle.
Manifestly, the piping necessary to convey the oil to and from the source
of vaporisation obstructs the rays emanating from certain sections of the mantle.
Burners of the second type include the Chance burner and the Scott
burner.
In the Chance burner the dual horizontal vaporising tubes are contained
in a metal chamber below the burner proper, and they are heated by a
subsidiary burner, deriving its gaseous supply from the product of vaporisation.
In the Scott burner (fig. 235), a series of subsidiary burners, inclosed
in a metal cover, heat the conducting tube in a vertical position. These