266
HARBOUR ENGINEERING.
tion is effected by the direct heat of the mantle, and for this purpose the
vaporising chamber, or tube, is placed close to and above the mantle. In the
other class, a separate heater is used for vaporisation. Obviously, tliis entails
additional apparatus; but, on the other hand, there is less interference with
the luminous range of the mantle. In all cases, some temporary source of
Em. 233. —Luchaire Burner. Fig. 234. —French Burner.
heat is required for a preliminary five or ten minutes, until the action of the
burner becomes automatic.
Burners of the first type include the Pintsch burner, the Matthews
burner, and the Luchaire burner, amongst those of German, English, and
French manufacture respectively.
In the first-named (fig. 231), the oil is forced under compressed air pres-
sure of 45 Ibs. per square inch into a metal chamber located immediately
above the mantle, whence, after vaporisation, it is conducted downwards to a
mixing chamber, where it is combined with air before passing into the burner.