Fuel
In order to cook foods, heat in some form must be applied. This heat
is obtained usually by burning some substance. Thus the first
requisite for obtaining heat is something to burn, i.e. a fuel. The
fuels commonly used in households are, wood, coal, kerosene, and
gas. Although electricity is not a fuel, its use in cooking is so
well established that it should be mentioned as a source of heat.
Heat; Kindling Temperature
There are fuel substances everywhere,--paper, cloth, wood, etc.
These materials do not burn unless heated; even gas does not burn by
simply turning on the stopcock. But if a piece of paper is placed in
contact with glowing iron, the paper burns. It burns because it is
heated. If the blazing paper is placed in contact with kindling wood
and coal, the kindling wood soon begins to burn because it is heated
by the burning paper. The coal burns when it is heated by the
burning wood. All fuels must be heated before they will burn.
When one thinks of the ease with which paper "catches fire" and of
the difficulty of making hard coal burn, it becomes evident that
some substances require only a small amount of heat before they will
burn, while others require much heat. Different materials, then,
require different degrees of heat to burn. The phosphorus and other
substances on the tip of a match ignite readily. The heat that is
developed by rubbing the tip over some surface is sufficient to make
the phosphorus burn. The burning phosphorus and other substances
heat the match stick to the temperature at which it begins to burn;
the burning match stick applied to paper heats the latter to the
temperature at which it burns. The temperature to which a substance
must be heated in order to burn and continue to burn is called the
kindling temperature of that substance.
Examination of a Coal Range
Remove the lids from the coal range. Note the location of the fire
box. What is its purpose? How is the floor of the fire box
constructed? Where is the check damper? What is its purpose? Where
is the ash pan? Where is the front damper? What is its purpose? Note
the place where the stovepipe joins the range. What is the purpose
of the stovepipe? Note the damper in the stovepipe. What is its
purpose? Note the location of the oven. By what is the oven
surrounded? Find the oven damper. Open it. In what direction do the
hot gases pass out when the oven damper is open? What part of the
range is heated when the oven damper is open?
Fire Building in a Coal Range
It is necessary to have the fire box, ash pan, and other parts of
the stove clean before building a fire. After cleaning, place a
generous layer of loosely crumpled paper over the bottom of the fire
box, then about four layers of kindling wood, placed so that there
are air passages between the pieces, and on top of the wood put two
shovelfuls of coal. Regulate the dampers for a direct draft, replace
the stove-lids, and brush the surface of the stove.
Before lighting the fuels, polish the range in the following manner:
To the nickel of the stove apply whiting and ammonia or any
satisfactory metal cleanser.
To the iron of the stove apply oil rather than "blacking." Light
paraffin oil may be used for this purpose. Apply the oil with cotton
waste, or a soft cloth. (Care should be taken not to apply an excess
of oil.) Polish with soft cotton or woolen cloth. One should
remember, however, that oil must be used with caution. It should
never be applied to a stove containing burning fuels. If the stove
cloth, saturated with oil, is not destroyed after using, it is well
to keep it in a covered tin can or stone jar. After polishing the
stove, light the fuels. When the wood is reduced to glowing embers
and the coal is burning, add more coal. If this burns well, change
the dampers to make an indirect draft.
Gas Ranges
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.
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.
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 can mix with the gas to
produce a blue flame.
Conserving Gas
According to authoritative information3, "the demands for natural
gas are now greater than the available supply. Food and trees can be
grown. Water supplies are constantly replenished by nature, but
there is no regeneration in natural gas." It is thought that natural
gas forms so slowly that millions of years will be required to make
the present concentrated supply. As far as we are concerned, when
the present supply is used up, it is gone forever. Since natural gas
is a most efficient fuel, every housekeeper and householder should
feel obligated to waste none of it. Suggestions for conserving gas
follow:
- See that the mixer is properly adjusted so that the flame is
light
blue in color.
- In selecting a gas stove, see that the burner is so located
that the
cooking surface is the correct distance above the burner. The
tip of the
flame should touch the bottom of the utensil. If it is necessary
to have a
long flame in order to bring this about, there is considerable
waste of
gas.
- If the flame is long, the gas pressure is greater than
necessary.
Regulate the gas pressure by adjusting the valve in the supply
pipe. A
short flame will save gas and produce satisfactory results,
provided the
cooking surface is the proper distance above the burner.
- After the contents of a cooking utensil boils, turn the gas
cock so
that only "gentle" boiling takes place. A food becomes no hotter
in
rapidly boiling than in gently boiling water.
- When possible, use the simmering burner rather than the
regular or
giant burner.
- Let the flame touch only the bottom of the cooking utensil.
There is a
wastage of gas when the flame streams lip the sides of the
cooking
utensil.
- Turn off the gas immediately when fuel is not needed.
Matches are
cheaper than fuel gas.
Care of the Gas Range
Daily Care
If any substance on the stove cannot be removed easily, loosen it
with a knife, and then wipe the stove with a newspaper. Clean the
stove with waste or a cloth having a little light paraffin oil on
it. Polish with soft cotton or flannel cloth. Remove the tray that
is beneath the top burners, and wash.
Weekly Care
Wash the inside of the oven and the movable tray with water to which
washing soda solution has been added. It is well to light the oven
burner to dry the stove after washing the ovens. Polish the nickel,
if necessary. Clean the stove with oil as directed for a coal range.
Since oils ignite most readily, care should be taken not to apply
the oil when the stove is lighted! Wipe the burner with the oil.
Clean the small holes of the burners by using a knitting needle or
wire kept for this purpose; or, if the openings in the burners are
slots, use a knife to clean them.
Stoves and Heating Devices
Kerosene Stoves
There are two types of kerosene stoves, viz., wick and wickless
stoves. The burners of the former type are supplied with cotton
wicks which become saturated with kerosene. When a match is applied
to the wick, the kerosene on it vaporizes and the vapor burns. The
burning kerosene vapor vaporizes more kerosene and thus the burning
continues.
In one type of wickless stove it is necessary to heat the burner so
that the kerosene will vaporize when it comes in contact with it.
Such a burner may be heated by pouring a small quantity of gasoline
into it. A lighter is then applied to the burner. When the latter is
sufficiently heated, the kerosene is turned on. The kerosene then
vaporizes as it flows into the hot burner and burns.
In other types of so-called wickless stoves, the burners are
equipped with asbestos or other incombustible material. This
material becomes saturated with kerosene and carries the fuel to the
tip of the burner somewhat as does a cloth wick.
It is especially necessary to keep kerosene burners clean. Bits of
carbon collect in them and prevent perfect combustion. This results
in "smoke" or soot issuing from the burner. It is well to keep the
burners and wicks free from charred material, and to renew the
latter when they become short.
Most kerosene stoves are equipped with removable containers for the
fuel. These should be kept filled with sufficient kerosene for
burning. A wick burner should never be allowed to burn after all the
kerosene in the container is exhausted.
Gasoline Stoves
When gasoline is used in a stove, it is necessary to vaporize the
gasoline before lighting the burner. This is accomplished in most
stoves by letting the gasoline flow into a cup situated underneath
the burner, turning off the supply of gasoline, and then applying a
match to the cup. By the time the gasoline is burned the burner is
heated. Then the stopcock is turned on, a match applied to the
burner, and the gasoline vaporizes and burns.
Gasoline burners, like those in which kerosene is burned, should be
kept clean. When a mixture of gasoline vapor and air is heated, an
explosion may result. It is for this reason that "the tank or
gasoline container of a stove should never be filled while the
burners of the stove are lighted or even hot."
Electric Stoves
It was mentioned previously that electricity is not a fuel. Hence
electric stoves are not provided with burners. They have heaters
which contain coils of wires through which an electric current
passes. Electricity is the cleanest source of heat for cooking. But
in order to operate an electric stove economically, it is necessary
to utilize the current required for a heating element to its
greatest extent. For example, if the current is turned on to heat
the oven as many foods as possible should be cooked in the oven. |
