Hinges and a hasp, or some device to hold the cover of the box shut, will be necessary, as the packing should be such that there is a little upward pressure on the cover.
A cushion is desirable to cover each kettle used, one which is thick enough to fill the hay-box after the kettle is in place. For making these cushions use muslin, denim, or any thing of the kind that is at hand, filling them, generally, with the same material as that used in packing the box. Shape them like a miniature mattress, joining two pieces which are the dimensions of the top of the box with a strip which is from two and one-half inches to four or five inches wide, the width depending upon the material with which the cushion is stuffed, some materials requiring thicker insulation than others.
Hay-Box With Two Compartments.
Partly packed compartment of hay-box, showing pail in place for packing. Cushion. “Space adjuster.” Small pail to fit in “space adjuster.”
Finished compartment of hay-box. Cushion. Large Pail. Pan and cover.
The packing material may be either hay, straw, paper, wool, mineral wool, excelsior, ground cork, Southern moss, sawdust, or any other non-conducting material that is adapted to filling the space between the kettle and the box. If hay is used, choose soft hay. Wool is, perhaps, the best heat retainer of those mentioned, and it is easy and pleasant to handle. Clean, soft wool may be purchased at woollen mills and elsewhere. It should cost about thirty-five cents a pound, but as it is very light it requires much less, by weight, than of some other cheaper materials. Mineral wool can be purchased at large hardware stores. It costs about five cents a pound, but about five times as many pounds are required as an equivalent for wool. Cheap cotton batting can be obtained at dry-goods stores; ground cork from large grocers. This is used by them as packing for grapes or other fancy fruits. Sawdust, obtainable at sawmills, and perhaps elsewhere, must be well dried before using. Excelsior is used by many kinds of merchants, and can be bought for about two cents a pound. Hay is plentiful in country places and can also be purchased at feed-stores in the cities. Southern moss, easily procurable in the Southern States, can be found at many upholsterers’ in the North as well. Newspapers and hair, such as is used by plasterers, are available in city and country.
The utensils. Perhaps the best shape for the cooking utensil, that is, one which will have the least possible radiating surface, is a pail about the depth of its own diameter. The sides should be straight and perpendicular to the bottom. The cover should fit securely into place. If a smaller utensil is to be used inside the large one, which is often a great convenience, it must not be so high that the cover of the larger pail will not go on. A “pudding pan” may be used for the inside utensil, resting on the rim of the pail; but care must be taken, with this arrangement, that a cover is secured that will fit the pan closely.
To select the material best adapted for cooker utensils one must consider its wearing quality, its heat-absorbing power, to some extent, and also the action upon it of the water, acids, salts, etc., which are found in the foods. For instance, iron utensils, as well as most tinware that has been used for any length of time, will rust with the long subjection to heat and moisture; acids will make a disagreeable taste with iron or old tin utensils; while acids in such long contact, with even new tin might also form poisonous tin salts in sufficient quantity to be decidedly injurious. Earthenware would seem ideal except that it is likely to break when over the flame. It is desirable that the covers be of the same material as the utensil, or of some other rust-proof material. It will pay to get the best, when buying these kettles, for they will last well, with reasonable care, and a poor utensil will soon be of no use whatever. Well-enameled iron, except for its weight, is good; also the best quality of agate ware, ordinary aluminum, or, perhaps best of all, for very large utensils at least, cast aluminum. Aluminum is expensive, but its light weight, excellently fitting parts, and lasting qualities commend it above other materials, and it will be found to pay in the end.
The size of the pails will depend to some extent upon the number of people to be served, although there is a minimum size, below which there is not a sufficient bulk of food to cook well. Under the heading “[Practical Suggestions on the Use of the Fireless Cooker],” this matter of quantity is more fully discussed. For a family of five or six persons a six-quart pail with a pan to fit inside of it has been found satisfactory. It will be convenient to have also a larger pail for large pieces of meat, such as hams.