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sands, each one of which has cost the labor of days, weeks, or months. 
They have called in requisition the services of the ablest scientific men 
and the most successful farmers. They have involved an incalculable 
amount of thought, care, and toil in the laboratory, the stable, and the 
study. The labor, much of it of a menial sort, has been performed will- 
ingly, even enthusiastically, by those to whom it has brought not wealth, 
but only meager support. Nor has the work been in vain. These 
investigations have done a vast deal to settle the questions about stock- 
feeding, which occupy so much space in the papers, and which are as per- 
plexing as they are important to millions of farmers on both sides of the 
Atlantic. Combined with the results of daily farm experience, they have 
shown for what purposes different kinds of fodder-materials are best 
fitted, and how much eachis worth. They have taught the farmers how 
to make valuable fodder out of poor hay and straw; how to employ 
lucerne, seradelia, clover, and other forage-crops to the best advantage ; 
how to utilize waste products suchas flax-seed and cotton-seed and the oil- 
cake made from them, also the refuse from the manufacture of sugar 
from beets, and of alcoholic spirits and starch from potatoes and grains. 
They have shown in what proportions these and scores of other fodder- 
materials should be mixed and used, so as to get the greatest benefit at 
the least cost.” In brief, this sort of work is supplying German farmers 
with just the information they need in order to keep their stock, and 
“produce meat, dairy-products, and whatever else comes from the main- 
taining of domestic animals, most rationally and with the largest profit. 
EXPERIMENTS IN VEGETABLE NUTRITION. 
While a very large part of the whole work of the European stations 
is devoted to the study of the nutrition of plants, to the ways in which 
their food is furnished by atmosphere, soils, and fertilizers, and used in 
their development, yet but comparatively few experiments are made on 
the growth of crops in the field. Experience has shown that the most 
reliable and useful results are obtained in the growing of plants in 
water containing various fertilizing materials in solution, or in artificial 
soils watered with such solutions. The influences to which the plant 
is subjected in its growth are thus under more perfect control, and 
the results, in a corresponding degree, more accurate and complete. 
‘Some of the substantial advantages that have been gained as the 
immediate outcome of the work of the experiment-stations” are summed 
up as follows by Professor Johnson: 
In respect to the food of plants, it has been settled that potash, lime, magnesia, iron, 
phosphoric acid, and sulphuric acid must be furnished to all agricultural plants through 
their roots and by the soil, in order to their growth. It has also beén shown that soda, 
silica, and chlorine are not needful for the early growth of grain-crops, but that chlorine is 
essential for the perfection of the seed, and that silica is probably necessary to uniform 
blossoming and ripening. It is further proved that water must enter crops through their 
roots ; that carbon, which constitutes more than half their wéight, is superabandantly. fur- 
nished by the air; that air and water together yield the materials out of whivh fully 90 to 
98 per cent. of crops is built up, and that the soil has to give for their nourishment but the 
2 to 8 per cent. of mineral matters which remain as ashes when they are burned, and the $ 
to 2 per cent. of nitrogen which they also contain. It is likewise definitely settled that 
nitrates in the soil are the chief natural source of nitrogen, while the ammonia of manures, 
as well as a variety of substances containing nitrogen, and found in urine or focmed in the 
decay of dead animals, likewise supply vegetation with nitrogen, 
The experiment-stations have further ascertained, by a multitude of trials, what quanti- 
ties and proportions of all these elements are needful to produce any given crop, and to 
what extent they are removed from the soil. On the other hand it has been determined what 
kinds of plant-food, and what quantities, are contained in the long list of manures and 
fertilizers, in all kinds of dung, urine, ashes, salts, guanos, phosphates, manufacturing 
refuse, &c. The remarkable quality of the soil to sift, as it were, some of the most 
