VARIETIES OF COAL.--Possibly the most common fuel used for cooking is coal. This fuel comes in two varieties, namely, anthracite, or hard coal, and bituminous, or soft coal. Their relative cost depends on the locality, the kind of stove, and an intelligent use of both stove and fuel. Hard coal costs much more in some places than soft coal, but it burns more slowly and evenly and gives off very little smoke. Soft coal heats more rapidly than hard coal, but it produces considerable smoke and makes a fire that does not last so long. Unless a stove is especially constructed for soft coal, it should not be used for this purpose, because the burning of soft coal will wear it out in a short time. The best plan is to use each variety of coal in a stove especially constructed for it, but if a housewife finds that she must at times do otherwise, she should realize that a different method of management and care of the stove is demanded.

SIZES OF COAL.--As the effect of coal on the stove must be taken into consideration in the buying of fuel, so the different sizes of hard coal must be known before the right kind can be selected. The sizes known as stove and egg coal, which range from about -/ to -/ inches in diameter, are intended for a furnace and should not be used in the kitchen stove for cooking purposes. Some persons who know how to use the size of coal known as pea, which is about / to / inch in diameter, like that kind, whereas others prefer the size called chestnut, which is about / inch to -/ inches in diameter. In reality, a mixture of these two, if properly used, makes the best and most easily regulated kitchen coal fire.

QUALITY OF COAL.--In addition to knowing the names, prices, and uses of the different kinds of coal, the housewife should be able to distinguish poor coal from good coal. In fact, proper care should be exercised in all purchasing, for the person who understands the quality of the thing to be purchased will be more likely to get full value for the money paid than the one who does not. About coal, it should be understood that good hard coal has a glossy black color and a bright surface, whereas poor coal contains slaty pieces. The quality of coal can also be determined from the ash that remains after it is burned. Large chunks or great quantities of ash indicate a poor quality of coal, and fine, powdery ash a good quality. Of course, even if the coal is of the right kind, poor results are often brought about by the bad management of a fire, whether in a furnace or a stove. Large manufacturing companies, whose business depends considerably on the proper kind of fuel, buy coal by the heat units--that is, according to the quantity of heat it will give off--and at some future time this plan may have to be followed in the private home, unless some other fuel is provided in the meantime.

Mixed with poor coal are certain unburnable materials that melt and stick together as it burns and form what are known as clinkers. Clinkers are very troublesome because they often adhere to the stove grate or the lining of the firebox. They generally form during the burning of an extremely hot fire, but the usual temperature of a kitchen fire does not produce clinkers unless the coal is of a very poor quality. Mixing oyster shells with coal of this kind often helps to prevent their formation.

COKE.--Another fuel that is sometimes used for cooking is coke. Formerly, coke was a by-product in the manufacture of illuminating gas, but now it is manufactured from coal for use as a fuel. Because of the nature of its composition, coke produces a very hot fire and is therefore favorable for rapid cooking, such as broiling. However, it is used more extensively in hotels and institutions than in kitchens where cooking is done on a small scale.