The kettle to be used for cooking should be durable and free from seams or crevices which are hard to clean. It should have perpendicular sides, and the cover should be as flat as possible and be provided with a deep lid fitting well down into the kettle, in order to retain the steam. A kettle holding about six quarts is a convenient size for general use.

Tinned iron kettles should not be used in a fireless cooker, for, although cheap, they are very apt to rust from the confined moisture.

Enamelware kettles are satisfactory.

EXTRA SOURCE OF HEAT

Fireless cookers are adapted to a much wider range of cooking if they are provided with an extra source of heat in the form of a soapstone, brick, or an iron plate which is heated and placed underneath the cooking kettle. This introduces a possible danger from fire, in case the hot stove plate should come into direct contact with inflammable packing material such as excelsior or paper. To avoid this danger, a metal lining must be provided for the nest in which the cooking vessels and stone are to be placed.

[Ill.u.s.tration: _Fig._ 42.--Tightly fitting lid]

COVERING PAD

A cushion, or pad, must be provided, to fill completely the s.p.a.ce between the top of the packing material and the cover of the box after the kettle is in place. This should be made of some heavy goods, such as denim, and stuffed with cotton, crumpled paper, or excelsior. Hay may be used, but it will be found more or less odorous. Figure 43 shows the vertical cross-section of a home-made fireless cooker.

[Ill.u.s.tration: _Fig._ 43.--Vertical cross-section of fireless cooker. A.

Outside container; B. packing or insulating material; C. metal lining of nest; D. cooking kettle; E. soapstone plate, or other source of heat; F.

pad of excelsior for covering top; G. hinged cover of outside container.]

DIRECTIONS FOR FIRELESS COOKER--NO. II

(Single Cooker)

Materials required: Galvanized iron can, No. 3, with a cover; some sawdust; a covered agate pail (to be used as a cooking pail); and two yards of denim; any old linen, cotton, or woollen material may be used instead of denim.

METHOD OF MAKING

Place loose sawdust in the bottom of the can to a depth of about three inches. Measure the depth of the cooking pail. Turn a fold two inches greater than this depth the entire length of the denim or other material and make a long bag. Lay the bag flat on the table and fill it with an even layer of sawdust, so that when completed it will still be half an inch wider than the depth of the pail. Roll the bag around the cooking pail, so that a smooth, firm nest is formed when the bag is placed upright in the can on the top of the sawdust. From the remaining denim or other material make a round, flat bag (the material will have to be pieced for this). Fill this bag with sawdust and use it on top of the cooking pail. The bags must be made and fitted into the can in such a way that there will be no open s.p.a.ces whatever between the sides of the cooking pail and the can, or between the top of the cooking pail and the cover of the can, through which the heat might escape.

DIRECTIONS FOR FIRELESS COOKER--NO. III

(Double Cooker)

Materials required: One long box and two square boxes; the long box must be large enough to hold the other two and still leave two inches of s.p.a.ce all around them; five and one-quarter yards of sheet asbestos one yard wide; two covered agate pails to be used as cooking pails; and about one yard of denim or other material.

METHOD OF MAKING

Line the bottoms and sides of all three boxes with sheet asbestos. In the bottom of the long box lay newspapers flat to a depth of about half an inch. Put two inches of sawdust on top of this layer of newspapers.

Place the two square boxes inside the long one, leaving at least two inches of s.p.a.ce between them. Fill all the s.p.a.ces between the boxes with sawdust. Tack strips of denim or other material so that they will cover all the s.p.a.ces that are filled with sawdust.

The outside box must have a hinged lid, which must be fastened down with a clasp. Line the lid with the sheet asbestos to within half an inch of the edge. Put a layer of sawdust one inch deep on top of the asbestos.

Tack a piece of denim or other material over the sawdust, still leaving the edge free and clear so that the cover may fit tightly; or the lid may be lined with asbestos and a denim pillow filled with sawdust made to fit tightly into the top of the box.

USE OF THE FIRELESS COOKER IN THE PREPARATION OF LUNCHES

The fireless cooker should prove very useful in the lunch equipment of rural schools, as its use should mean economy of fuel, utensils, time, and effort. It might be made by the pupils and would afford an excellent manual training exercise.

Many of the dishes in the recipes given may be cooked in this way, but more time must be allowed for cooking, as there is a fall of temperature in placing the food in the cooker. When the vessel is being transferred from the stove to the cooker, the latter should be in a convenient position, and the transfer should be made, and the cushion placed in position, very quickly, so that the food will continue boiling. If the quant.i.ty of food is small, it should be placed in a smaller tightly covered pail, set on an inverted pan in the larger pail, and surrounded with boiling water. When there is an air s.p.a.ce above the food in the cooking dish, there is greater loss of heat, as air gives off heat more readily than water.

The following are examples of the foods that may be cooked in a Fireless Cooker:

Apple sauce--Bring to boiling temperature and place in the cooker, leave two hours.

Apple compote--Cut the apples in halves or quarters so that they need not be turned. Leave them in the cooker about three hours.

Dried fruits--Soak overnight, bring to the boiling-point, and leave in the cooker at least three hours.

Cream of wheat--Boil until thick, place in the cooker, leave overnight and, if necessary, re-heat in double boiler before using.

Rolled oats--Boil five minutes, then place in the cooker. Leave at least three hours and longer if possible.

Macaroni--Boil, then place in the cooker for two hours.

Rice--Boil, then place in the cooker for one hour.

All vegetables may be cooked in the cooker. They must be given time according to their age. A safe rule for all green vegetables is to allow two and a half times as long as if boiled on the stove.

In the home, where the cooking is much greater in amount than it can be in the school, the saving in fuel, by the judicious use of the properly made fireless cooker, is correspondingly much larger. For example: in soups, from 2-1/2 to 3-1/2 hours use of fuel is made unnecessary; pot roast 2-1/2 hours; beef stew 2-1/2 hours; lamb stew 1-1/2 hours; corn beef and cabbage 2-1/2 hours; baked beans 5-1/2 to 7-1/2 hours; chicken frica.s.see 2 hours; dried peas, beans, and lentils 3 hours; dried fruits 3 hours; rice pudding 1-1/2 hours.