Pumpkins, Squashes, Broom-Corn Seeds, Weeds, etc. Professor Storer has also analyzed several specimens of pumpkins and squashes, and finds them, on the whole, quite rich in nitrogen. He considers the pumpkin as "competent to supply a good part of the albuminoid matters which corn-stalks lack." Professor Storer also gives a large number of analyses of seeds of broom-corn, of weeds occasionally used as human food-as the dandelion, nettle, common plantain, purslane, and pigweed—and of blue-joint grass and reed canary-grass; for the broom-corn seeds are inferior to oats, etc., as food for stock, because poor in albuminoids though rich in carbohydrates. The weeds have considerable fodder value, but are unfit for cultivation because they are inferior to the plants with which they would have to come in competition. Still when gathered, as they often are, they ought to be saved and fed rather than composted, burned, or thrown away. The blue-joint grass was poor; but the reed canary-grass proved much better than was expected, is measurably rich in nutritive ingredients, and "as a substitute for our wild bog grasses it could doubtless be grown with advantage in numberless localities in this country" (Bulletin of the Bussey Institution, ii., 51, 81, 115, and 130).

Sugar-Beet Culture and Beet-Sugar Making.

The attempts in this direction in the United States have not thus far proved strikingly successful, though favorable reports come from California and elsewhere. One great trouble has been the putting-up of costly factories before the supply of beets good enough to pay for the working was made sure of.

Mr. H. C. Humphrey, who has made this subject, from the chemical standpoint especially, a study for several years, in this country and in Europe, has joined with Mr. Joseph Wharton in a very extensive experiment upon the estate of the latter in Balsto, N. J. The raising of the beets is being first tested, though a small experimental factory for making the sugar has been erected. Concerning the prospects of profitable manufacture, Mr. Humphrey makes estimates in brief as follows: A manufactory to consume 15,000,000 pounds of beets in one hundred days would cost about $60,000,

and the stock of bone-black $2250. The current annual expenses, including labor, materials, and incidentals, reckoning beets at $4 per ton, and interest on capital at 7 per cent., would be some $82,664. The returns for sugar, presscake, molasses, and residues for fertilizers, reckoning sugar to yield 8 per cent. of weight of beets, and to bring 84 cents per pound, and press-cake at $4 per ton, would be $107,233, leaving a profit of $24,569. This Mr. Humphrey considers high for probable expenses and low for returns.

NUTRITION OF ANIMALS.-STOCK-FEEDING.

The experimental investigations in this direction are increasing in number, range, scientific accuracy, and practical value. Nearly all of the most useful work of the past year has been done in the German experiment stations. Little that is absolutely new in principle has been discovered, but much has been done to establish, amplify, and make capable of wider application in practice the principles already propounded.

Sources of the Fat of the Animal Body.

It is common to see the albuminoids of foods classed as "flesh-formers," and the carbohydrates as "fat-formers." This is in accordance with the theory of Liebig, that, aside from the fats of the food, the carbohydrates sugar, starch, etc., are the main source of the fats of the body and the milk. But of late many physiologists-notably Voit-have maintained that animals get their fat from the albuminoids, and not from the carbohydrates of their food. It is well settled that the albuminoids can and do by their decomposition supply a good deal of fat for storing in the body and making milk. Whether the carbohydrates do the same is still an open question. Professor Wolff, in his lately published "Ernährung der Landwirthschaftlichen Nutzthiere" (Nutrition of Animals Useful in Agriculture), gives a very comprehensive summary of the latest experimental evidence upon the subject, from which he concludes that carnivora cannot, herbivora may, and swine probably do, produce fat from the carbohydrates of the food. Professor Henneberg, at the meeting of German naturalists and physicians at Hamburg in 1876,

expressed his opinion that fat is formed from carbohydrates by swine; and this would probably prove to be the case with other animals. With this view Dr. Gilbert, of Rothamstead, seemed to agree. Henneberg, on the same occasion, presented some calculations which led to the inference that 100 parts of albuminoids may produce 51.4 parts of fats.

Effect of Fodder upon Milk Production.

The experiments of Kühn at Moeckern on the effects of different kinds and amounts of food upon the production of milk by cows are coming to assume great importance. Eight series made during the years 1867-74 have now been reported. These include eighty-four single experiments with twenty-six cows. Detailed accounts of those of 1870-73 were commenced in the Journal für Landwirthschaft for 1874, and have just been completed in the volume for 1877. Only a brief report of the eighth series has been published. The later ones are not yet published. Dr. Kühn has, however, given, in a report of the work of the Moeckern station to 1877 (Landw. Vers. Stat., xxii., 133-143), a summary of results to that time. It appears that after the ration has reached a certain amount of food of fitting composition, (1) increase of the food brings an increase of the total yield of milk; (2) the "richness" of the milk, the percentage of dry or solid matters, increases at the same time; (3) there is a limit to this improvement in quality and amount of the milk, varying with different breeds and individuals; (4) changes in the composition of the rations, in the proportions of albuminoids, carbohydrates, and fats they contain, do not produce corresponding changes in the composition of the solid matters of the milk. The proportions of casein, albumen, fat, and sugar rise and fall parallel with each other; at least, the variations are slight, and not parallel with those in the ingredients of the food.

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In short, it does not seem practicable, by altering the quality of the food, to increase, for instance, the fat at the expense of the casein of the milk; to change a cheese cow" into a butter cow, or vice versa. A few exceptions to this rule have indeed been found. Two cows out of thirty experimented upon at Moeckern and Hohenheim have shown an evident and some others an apparent relative increase in

the fat of the milk when material rich in albuminoids, particularly palm-cake freed from oil, was added to the ration.

Changes in the Milk during the Period of Lactation. The Moeckern experiments have also given more accurate data upon this subject than have been ever before obtained. In general, the total yield of milk decreases as the milking period advances. The shrinkage is exaggerated by poor feeding, and can be prevented in part by adequate food and consequent maintenance of the body in good condition. The richness of the milk, the percentage of solids, increases. The increase can be aided by proper feeding, and partly prevented by inadequate nourishment and consequent falling-off in condition. As regards the changes in relative proportions of solid matters, their ratios to each other, the proportion of fat seems to decrease and that of casein to increase somewhat; that of albumen diminishes, while the sugar remains constant.

GENERAL CONCLUSIONS FROM EXPERIMENTS ON EFFECTS OF FOOD UPON MILK PRODUCTION.

Among the general principles deducible from the later experimenting on milk-production by cows, two of the weightiest are that of the food ingredients the most important as factors of the milk-production are the albuminoids, and that the production is controlled to a much greater extent than is commonly supposed by the bodily condition. And these two principles are, in fact, corollaries of the single, broader one developed by late research in this department of animal physiology-that the function of the lacteal glands is not entirely, or even mainly, that of filters through which certain ingredients of the blood are secreted as milk, but that they themselves produce, by metamorphosis of their own substance, the larger part of the solids of the milk; that, as Voit says, "the milk is essentially this organ, liquefied by fatty degeneration." It seems fairly well settled that all the casein and a good part of the fat and sugar of the milk are products of metamorphosis of the milk glands; that of the fat and sugar supplied by the blood, a portion results from similar metamorphoses in other parts of the body; and hence only a small residue of fat and sugar can come directly from the food.

Accordingly, to effect any considerable changes in the milk, we must first work upon the body, and provide it, and particularly the milk glands, with material for making the milk; and since albuminoids are the chief tissue-formers, they are most important for producing casein and fat in the milk. It is clear, then, that to produce a good yield of milk the animal must be kept in good condition by proper feeding; that the food, to be most economical, must contain the proper proportions of albuminoids, carbohydrates, and fats; and that the composition of the milk is decided by the peculiarities of the breed and individual rather than by the food. The practical application of these principles is apparent. For quality of milk select proper breeds; for amount, good milkers. Suit the food to the wants of the animal, and feed well, but not over richly.

Other Feeding Experiments.

Of those reported during the past year we have only space for the briefest reference to some of the most important. Among them are experiments on the digestive capacity of the horse, by Wolff, at Hohenheim; on the digestion of various foods by sheep, by Weiske at Proskau, Wolff and Kellner at Hohenheim, and Wildt at Kuschen; and on the digestion of different foods by swine, by Wolff, by Wildt, and by Heiden, at Pommritz. Full accounts of these are given in the volumes of the Landwirthschaftliche Versuchs-Stationen Journal für Landwirthschaft, and Landwirthschaftliche Jahrbücher for 1876 and 1877.

The Digestive Capacity of Horses.

Wolff reports experiments on the digestion of hay, straw, and oats by a horse as compared with sheep. The horse digested a little less from the hay and straw than the sheep. With oats the digestion was essentially the same by both. From his own and other experiments Wolff concludes that all the domestic animals-horses, cows, sheep, goats, and swine-digest the concentrated food (grain, roots, etc.) and the young succulent forage plants about alike. Of coarse foods, sheep digest a somewhat larger percentage than horses.