65. GENERAL CONSTRUCTION.--In Fig. 3 is illustrated the general
construction of the type of coal stove used for cooking. The principal
parts of such a stove, which is commonly referred to as a _cook stove_,
or range, are the firebox _a_; the grate _b_; the ash pit _c_, which
usually contains an ash-pan _d_; the oven _e_; the dampers _f_, _g_,
_h_, and _i_; the flue opening _j_ and flue _k_; openings in the top and
suitable lids, not shown, for kettles and pans; and the air space
extending from the firebox around three sides of the oven, as shown by
the arrows. To prevent the stove from wearing out rapidly, the firebox,
in which the fuel is burned, is lined with a material, such as fireclay,
that will withstand great heat. The fire in the firebox is supported by
the grate, which is in the form of metal teeth or bars, so as to permit
air to pass through the fuel from underneath. The grate is usually so
constructed that when the fire is raked it permits burnt coal or ashes
to fall into the ash-pan, by means of which they can be readily removed
from the stove. The oven, which lies directly back of the firebox and is
really an enclosed chamber in which food may be cooked, receives its
heat from the hot air that passes around it. The dampers are devices
that control the flow of air in and out of the stove. Those shown at _f_
and _g_ serve to admit fresh air into the stove or to keep it out, and
those shown at _h_ and _i_ serve to keep heated air in the stove or to
permit it to pass out through the flue.
[Illustration: Fig. 3]
66. Building a Coal Fire.--To build a coal fire is a simple matter. So
that the draft will be right for rapid combustion, it is first necessary
to close the dampers _f_ and _h _and to open the bottom damper _g_ and
the chimney damper _i_. With these dampers arranged, place crushed paper
or shavings on the grate; then on top of the paper or shavings place
kindling, and on top of the kindling put a small quantity of coal. Be
careful to place the fuel on the grate loosely enough to permit currents
of air to pass through it, because it will not burn readily if it is
closely packed. Light the fire by inserting a flame from below. When
this is done, the flame will rise and ignite the kindling, and this, in
turn, will cause the coal to take fire. When the fire is burning well,
close the dampers _g_ and _i_ so that the fuel will not burn too rapidly
and the heat will surround the oven instead of passing up the chimney;
also, before too much of the first supply of coal is burned out, add a
new supply, but be sure that the coal is sufficiently ignited before the
new supply is added so as not to smother the fire. If only a thin layer
is added each time, this danger will be removed. Experience has proved
that the best results are secured if the fire is built only 4 inches
high. When hot coals come near the top of the stove, the lids are
likely to warp and crack from the heat and the cooking will not be done
any more effectively. Another thing to avoid in connection with a fire
is the accumulation of ashes. The ash-pan should be kept as nearly empty
as possible, for a full ash-pan will check the draft and cause the grate
in the firebox to burn out.
67. ADJUSTING THE DAMPERS.--To get the best results from a cook stove,
and at the same time overcome the wasting of fuel, the ways in which to
adjust the dampers should be fully known. If it is desired to heat the
oven for baking, close dampers _f_ and _i_ and open dampers _g_ and _h_.
With the dampers so arranged, the heated air above the fire is forced
around the oven and up the flue, as is clearly shown by the arrows in
Fig. 3. A study of this diagram will readily show that the lower
left-hand corner of the oven is its coolest part, since the heated air
does not reach this place directly, and that the top center is the
hottest part, because the hottest air passes directly over this portion
of the oven and the heated air in the oven rises to it.
[Illustration: Fig. 4]
If it is desired to heat the surface of the stove, so that cooking may
be done on top of it, close dampers _f_, _h_, and _i_ and open damper
_g_. With the dampers so arranged, the heated air does not pass around
the oven, but is confined in the space above it and the firebox, as
shown in Fig. 4. While the damper _i_ in the flue is closed in order to
confine the heated air as much as possible to the space under the top of
the stove, it contains openings that allow just enough air to pass up
the flue to maintain the draft necessary for combustion. When the
dampers are arranged as mentioned, the hottest place on the surface of
the stove is between the firebox and the stovepipe, and the coolest
place is behind the damper _h_.
68. BANKING A COAL FIRE.--To economize in the use of fuel, as well as to
save the labor involved in building a new fire, it is advisable to keep
a fire burning low from one meal to another and from one day to the
next. As the nature of hard coal is such that it will hold fire for a
long time, this can be done by what is called _banking_ the fire. To
achieve this, after the fire has served to cook a meal, shake the ashes
out of the grate so that the glowing coals are left. Then put fresh coal
on this bed of coals, and, with the dampers arranged as for building a
new fire, allow the coal to burn well for a short time. Finally, cover
the fire with a layer of fine coal and adjust the dampers properly; that
is, close dampers _g_ and _h_ and open dampers _f_ and _i_. If the
banking is carefully done the fire should last 8 or 10 hours without
further attention. Care should be taken, however, to use sufficient coal
in banking the fire, so that when it is to be used again the coal will
not be completely burned, but enough burning coals will remain to ignite
a fresh supply. When the fire is to be used again, rake it slightly, put
a thin layer of coal over the top, and arrange the dampers as for
starting a fire. As soon as this layer of coal has begun to burn, add
more until the fire is in good condition.