Page:Popular Science Monthly Volume 25.djvu/229

This page has been validated.

sions, and changed into a gray, tough, elastic, and viscous or glutinous substance, which has been compared to bird-lime, and has received the appropriate name of gluten. When dried, it becomes a hard, horny, transparent mass. It is insoluble in cold water, and partly soluble in hot water. It is soluble in strong vinegar, and in weak solutions of potash or soda. If the alkaline solution is neutralized by an acid, the gluten is precipitated.

If crude gluten obtained as above is subjected to the action of hot alcohol it is separated into two distinct substances, one soluble and the other insoluble. As the solution cools, a further separation takes place of a substance soluble in hot alcohol, but not in cold, and another soluble in either hot or cold alcohol. The first—viz., that insoluble in either hot or cold alcohol—has been named gluten-fibrin; that soluble in hot alcohol, but not in cold, gluten-casein; and that soluble in either hot or cold alcohol, gluten. I give these names and explain them, as my readers may be otherwise puzzled by meeting them in books where they are used without explanation, especially as there is another substance, presently to be described, to which the name of vegetable casein has also been applied. The gluten-fibrin is supposed to correspond with blood-fibrin, gluten-casein with animal casein, and gluten with albumen.—Knowledge.


THE preservation of green fodder in the form of ensilage is now attracting so large a share of the attention of practical farmers, that a brief sketch of the history of the process, and an outline of the known facts in regard to fermentation, must be of interest to the general reader, as well as the student who wishes to trace the laws of evolution in the development of improved methods in agriculture.

Nearly thirty years ago, Adolf Reihlen, who owned a sugar-factory near Stuttgart, in Germany, preserved a crop of fodder-corn, which had been injured by frost, by burying it in trenches or pits, and covering it with the soil thrown out to protect it from the atmosphere. This method of preserving corn-fodder was suggested by the well-known process of making "brown or sour hay" by packing newly-cut grass in pits, which had been practiced for many years by farmers in Europe.

When the pits were opened, several months afterward, the fodder-corn had a greenish color and a peculiar odor, but its value as cattle-food was not apparently diminished. M. Reihlen was so well pleased with the results of his experiment, that he made a practice of "pitting" a quantity of fodder-corn every year, to obtain a supply of succulent feed for his cattle during the winter.