This section is from the book "Food Facts For The Home-Maker", by Lucile Stimson Harvey. Also available from Amazon: Food facts for the home-maker.
Eggs are not as economical a food as milk, and when they soar in price to ninety cents and a dollar a dozen, they should be kept for children and invalids by families who wish to keep the cost of food down. They are valuable as being a light, easily digested, nitrogenous food, capable of being used either raw or in many varied combinations.
Value of skimmed milk
It should be remembered in cooking eggs, no matter what the process may be, that the temperature should be kept low. Protein material when heated to the boiling point of water becomes tough and leathery, while it solidifies into a jellylike mass at 175o F. In order, then, to cook an egg without having it become tough, it should be kept below the boiling point of water. When the egg is in the shell this is done by dropping it into boiling water and allowing it to stand away from the fire the length of time desired according to the various tastes of the family, the size of the pan used, and the quantity of water - four minutes for a very soft egg, five or six minutes for a harder one. They should never be boiled. The same is true of a poached egg. In order to obtain a "hard-boiled" egg, the egg may be left in warm water twenty minutes. All custards also and even scrambled eggs are better when cooked in the top of a double boiler.
Eggs should be kept at a low temperature, but not below freezing point. As they readily absorb odors and flavors from surrounding substances, it is well to remove them from the paper box in which they usually are shipped and place them in a clean china bowl. In order to preserve them for some months, they may be placed in large crocks and entirely submersed in a mixture of boiled, cooled water and water glass (sodium silicate), one part of the water glass to nine parts of water. This merely coats the surface of the egg, thereby preventing the evaporation of the air from the inside and the entrance of germs through the pores of the shell from the outside.
How to cook eggs
Care of eggs
 
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