and its burner (if there is one). (_i_) Supply pipe. (_j_)
Stovepipe.

The method of lighting oven burners varies in different ranges, and for
this reason it is impossible to give directions for lighting which will
apply to all oven burners. There is, however, one important direction that
should always be borne in mind. _Always open the oven door before
lighting the oven burners._ If such caution is not observed, the gas
may escape into the oven and cause an explosion. In case there is a pilot-
lighter, open the oven door and see that the oven burners are turned off
before lighting the pilot.

[Illustration: Courtesy of Clark Stove Co FIGURE 13--GAS BURNERS A,
giant, B, regular, C, simmering]

ADJUSTING A GAS BURNER.--The products of combustion of fuel gas that most
interest the housekeeper are carbon and carbon dioxide. Carbon dioxide is
not a poisonous gas, but it does not support animal life. Air containing
much carbon dioxide does not contain enough oxygen for perfect
respiration, hence the need of an outlet for the products of combustion of
a gas stove; good flue construction is quite as necessary for a gas range
as for a coal range (see Figure 14).

When gas burns with a yellow flame, it deposits soot on cooking utensils
and does not give as much heat as it should. This is caused by incomplete
combustion. Moreover, _carbon monoxide_, which is present in some
gas, may escape without burning. This is an exceedingly poisonous gas and
when inhaled even in small quantities may cause serious effects. Hence it
is specially necessary for a housewife to see that the gas burner is
clean, well regulated, and properly constructed, so that sufficient air