drain, and which is made to fit into her dishpan. Fitting the dishes into this, she is able to immerse. them in hot rinsing water, and then lift them out to dry. She finds the plan an excellent one.

Another student writes that she has found sifted coal ashes a most useful article to use in cleaning knives. Another prefers sifted wood ashes. These most be very carefully sifted, so that no hard bits be left in, which might scratch the articles polished.

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The kitchen dishes are usually the most difficult to wash, and one student describes a home-made scrubber" which she declares is very useful. “Take a broom apart, a good one, by removing the wire and letting the straw loose," she says. "The upper part of the straw is then put into boiling water and left long enough to soften it. Then the straws are tied together in bundles about two inches across, using a strong twine. The twine is pulled tight, and sinks into the softened straw, and when dry, it does not slip. A loop is left for hanging the bundle, and the straw is left its whole length. These are so long and slender they will reach into anything. They are a great saving on the hands, and allow the use of much hotter water."

Many of our students recommend the use of soft paper in cleaning greasy dishes, kettles, and pans, The papers may be burned, thus disposing of much grease which would otherwise find its way into the kitchen sink drain.

LATENT HEAT

The subject of latent heat, described on page 12, has proved very puzzling to many. It is certainly a strange idea at first, that heat does anything more than make things warm. Still, a moment's consideration recalls to mind that heat can do many other things. Heat causes chemical change, for substances are often changed by strong heat. Heat causes most substances to expand. If a sealed can of any substance is strongly heated, it will probably explode. Heat causes liquids to evaporate, and solids to melt.

If a liquid is placed in an open dish on a source of heat, its temperature will rise until it begins to boil. After this, it gets no hotter, no matter how much heat is applied, unless the liquid is becoming more dense as it boils, as would be the case with a syrup, for example. The heat it receives is all expended in changing the liquid into vapor, or, as we say, changing the "state of matter." The particles (molecules) are driven farther apart by the heat. cubic inch of water makes a cubic foot of steam. The amount of heat necessary to produce the change from liquid to gas varies with different substances. Water requires a very large amount. Four times as much heat is required to change an ounce of water into steam as to vaporize the same amount of alcohol. If heat is applied rapidly, the liquid will boil rapidly, but it does not affect the temperature. The heat

used in this way is not lost, but is stored up in the vapor as latent heat. The steam is no hotter than the boiling water, and heat added keeps it from becoming liquid. When vapor condenses and changes back to liquid, the latent heat is given out, and warms surrounding things. In fact, the vapor cannot condense unless the latent heat it contains is removed, except under pressure. This latent heat makes steam an excellent medium for heating buildings, as it contains so much heat and passes through pipes rapidly. Not only is the steam itself hot, but it carries a vast amount of heat stored up, to be liberated in the cooler regions.

Latent heat is stored up in water, also, and is liberated when the water becomes ice. This is seldom apparent, for far less heat is thus stored in water than in steam, and, too, the temperature of freezing water is low. The heat given out when water freezes is at 32° F, while that given out when steam condenses is at 212° F. Still, a cellar may be several degrees warmer if it contains a tank of water which freezes than if the water were not there. The temperature may keep about 32° F. where otherwise it might go to 26° or less.

A room is cooled in warm weather by sprinkling water upon the floor. The evaporation of the water takes much heat from the air, storing it in the

vapor produced. Britannia and some other metals of which pitchers, teapots, etc., are made will melt if placed on a hot stove. If, however, they contain water, this is not likely to occur, for the water cannot be heated above its boiling point, and this is far below the melting point of the metal, and keeps the temperature of the metal low enough for safety. This reminds me of an experiment I once saw where candy was actually made in a pasteboard box. The syrup never became hot enough to scorch the paper, and thus the paper itself was kept fairly cool.

USE OF THE THERMOMETER

A kitchen thermometer may be bought of any dealer in the better class of kitchen goods. The floating dairy thermometers are convenient. One to register 212° F, may be obtained from the School for 50 cents. A thermometer made to register oven temperatures is more expensive, one registering to 600° F. costing $1.50. Various uses of the thermometer are described in Principles of Cookery and Home Care of the Sick, but there are many times in the kitchen when it is of assistance, as in getting the right density for syrups in candy making, for syrups in preserving, and the right temperatures for raising bread, making soups, custards, etc.

Some uses of the thermometer in the kitchen are the following, described in Miss Parloa's "Home Economics":

Olive oil is liquid above 75°. If above this temperature it shows solid specks, making it look cloudy, you may be sure it is adulterated with some fat having a higher melting point.

Butter should melt at 94°. If it does not, you may know it is adulterated with suet or some other fat having a higher melting point.

BREAD MAKING

The composition and manufacture of bread are subjects which have been given much study. The carbon dioxide which serves to lighten the dough raised with yeast is produced at the expense of some of the starch of the flour. This starch is completely driven from the loaf as carbon dioxide gas and alcohol during the baking. The loss is estimated at about 2 per cent. Attempts have been made in large bakeries to save the alcohol, but no economical method has been devised. About fifty years ago, German chemists in studying the question estimated that the food materials lost in twentyfour hours, when bread is raised with yeast, was sufficient to supply bread to 400,000 people! These figures were certainly startling to the thrifty Germans, and the possibility of producing the carbon dioxide gas in some less extravagant manner was studied with considerable care in German laboratories, and also at Harvard University in America. Baking