Diggers in the Earth

by Eva March Tappan

There are a good many reasons why aluminum is useful. As has been said it is strong and light and does not rust in moisture. You can beat it into sheets as thin as gold leaf, and you can draw it into the finest wire. It is softer than silver, and it can be punched into almost any form. It is the most accommodating of metals. You can hammer it in the cold until it becomes as hard as soft iron. Then, if you need to have it soft again, it will become so by melting. It takes a fine polish and is not affected, as silver is, by the fumes which are thrown off by burning coal; and so keeps its color when silver would turn black. Salt water does not hurt it in the least, and few of the acids affect it. Another good quality is that it conducts electricity excellently. It is true that copper will do the same work with a smaller wire; but the aluminum is much lighter and so cheap that the larger wire of aluminum costs less than the smaller one of copper, and its use for this purpose is on the increase. It conducts heat as well as silver. If you put one spoon of aluminum, one of silver, and one that is "plated" into a cup of hot water, the handles of the first two will almost burn your fingers before the third is at all uncomfortable to touch.

A "MOVIE" OF AN ALUMINUM FUNNEL
Courtesy The Aluminum Cooking Utensil Company.
Seventeen other operations are necessary after the thirteenth stamping operation before the funnel is ready to be sold. And after all this work, we can buy it for 35 cents at any hardware store.

Aluminum is found not only in clay and indeed in most rocks except sandstone and limestone, but also in several of the precious stones, in the yellow topaz, the blue sapphire and lapis-lazuli, and the red garnet and ruby. It might look down upon some of its metallic relatives, but it is friendly with them all, and perfectly willing to form alloys with most of them. A single ounce of it put into a ton of steel as the latter is being poured out will drive away the gases which often make little holes in castings. Mixed with copper it makes a beautiful bronze which has the yellow gleam of gold, but is hard to work. When a piece of jewelry looks like gold, but is sold at too low a price to be "real," it may be aluminum bronze, very pretty at first, but before long its luster will vanish. Aluminum bronze is not good for jewelry, but it is good for many uses, especially for bearings in machinery. Aluminum mixed with even a very little silver has the color and brightness of silver. The most common alloys with aluminum are zinc, copper, and manganese, but in such small quantities that they do not change its appearance.

With so many good qualities and so few bad ones, it is small wonder that aluminum is employed for more purposes than can be counted. A very few years ago it was only an interesting curiosity, but now it is one of the hardest-worked metals. Automobiles in particular owe a great deal to its help. When they first began to be common, in 1904-05, the engines were less powerful than they are now made, and aluminum was largely employed in order to lessen the weight. Before long it was in use for carburetors, bodies, gear-boxes, fenders, hoods, and many other parts of the machine. Makers of electric apparatus use aluminum instead of brass. The frames of opera glasses and of cameras are made of it. Travelers and soldiers and campers, people to whom every extra ounce of weight counts, are glad enough to have dishes of aluminum. The accommodating metal is even used for "wallpaper," and threads of it are combined with silk to give a specially brilliant effect on the stage. It can be made into a paint which will protect iron from rust; and will make woodwork partially fireproof.

Aluminum has been gladly employed by the manufacturers of all sorts of articles, but nowhere has its welcome been more cordial than in the kitchen. Any one who has ever lifted the heavy iron kettles which were in use not so very many years ago will realize what an improvement it is to have kettles made of aluminum. But aluminum has other advantages besides its lightness. If any food containing a weak acid, like vinegar and water, is put into a copper kettle, some of the copper dissolves and goes into the food; acid does not affect aluminum except to brighten it if it has been discolored by an alkali like soda. "Tin" dishes, so called, are only iron with a coating of tin. The tin soon wears off, and the iron rusts; aluminum does not rust in moisture. A strong alkali will destroy it, but no alkali in common use in the kitchen is strong enough to do more harm than to change the color, and a weak acid will restore that. Enameled ware, especially if it is white, looks dainty and attractive; but the enamel is likely to chip off, and, too, if the dish "boils dry," the food in it and the dish itself are spoiled. Aluminum never chips, and it holds the heat in such a manner as to make all parts of the dish equally hot. Food, then, is not so likely to "burn down," but if it does, only the part that sticks will taste scorched; and no matter how many times a dish "boils dry," it will never break. If you make a dent in it, you can easily pound it back into shape again. It is said that an aluminum teakettle one sixteenth of an inch in diameter can be bent almost double before it will break.

Aluminum dishes are made in two ways. Sometimes they are cast, and sometimes they are drawn on a machine. If one is to be smaller at the top, as in the case of a coffeepot, it is drawn out into a cylinder, then put on a revolving spindle. As it whirls around, a tool is held against it wherever it is to be made smaller, and very soon the coffeepot is in shape. The spout is soldered on, but even the solder is made chiefly of aluminum.

Aluminum dishes may become battered and bruised, but they need never be thrown away. There is an old story of some enchanted slippers which brought misfortune to whoever owned them. The man who possessed them tried his best to get rid of the troublesome articles, but they always returned. So it is with an aluminum dish. Bend it, burn it, put acid into it, do what you will to get rid of it, but like the slippers it remains with you. Unlike them, however, it brings good fortune, because it saves time and trouble and patience and money.