FERTILIZERS. 79 



once determined those requirements for his particular lands, important information has thus 

 been obtained and much been accomplished toward successful results. 



Prof. Johnson, of Yale College, the author of several agricultural works, and chemist of 

 the Connecticut Experiment Station, suggests that in making such experiments, it is better to 

 have a long and narrow plot of ten or fifteen square rods area to experiment upon, because 

 the inequalities of the soil are less liable to disturb the results. The land being prepared for 

 a crop, a number of measured plots or strips are laid off, and different fertilizing materials 

 are applied to them in appropriate quantities. On one, for example, use gypsum; on another, 

 fresh slacked lime ; on another, a superphosphate made from bone-ash or bone-black, or 

 ground bones ; on another, pulverized blood and meat-scraps, rich in nitrogen, but nearly 

 free from phosphates; on another, sulphate ammonia; on a sixth, muriate of potash; seventh, 

 a nitrogenous phosphate or a fish guano ; eighth, stable manure, etc. Two or three plots with 

 no manure should intervene to make a basis of comparison. The experiments should extend 

 over a series of three or four years, the same plots being each year treated with the same 

 kinds and qualities of fertilizers, but cultivated with different crops. Different fertilizing 

 materials, or the combination of certain substances to form special fertilizers for special 

 crops, could thus be tested. Mr. Lawes, of Rothamsted, states that in order to obtain large 

 crops he would use artificial fertilizers. Prof. Ville, the noted French agricultural chemist, 

 concurs in the same opinion from his numerous experiments. For speedy results, when 

 skillfully used, and for restoring partially-exhausted lands, rendered so by over-cropping, 

 commercial fertilizers, when properly used, are among the most valuable agents of the farmer. 

 By combining stable manure and commercial fertilizers, we think the result in all respects 

 will prove perfectly satisfactory. 



Since commercial fertilizers are so frequently adulterated with worthless substances, it is 

 safe to purchase only those manufactured by some well-known firm of reputed integrity, 

 whose products have been well-tested in the markets, or after a sample has been subjected to 

 chemical analysis by a competent chemist. The principal deficiencies of our soils, as we have 

 previously stated, are potash, phosphoric acid, and nitrogen, with often a lack of sulphuric 

 acid, lime, and rarely magnesia. In England, according to Mr. Lawes, nature has furnished, 

 generally, a sufficient supply of potash, and consequently the soils there do not require it 

 artificially to the extent that those of the United States do, the principal demand there being 

 nitrogen ; consequently the tests of English soils will not always apply definitely to our own 

 in the production of certain crops; yet, notwithstanding, these tests of foreign soils serve to 

 illustrate the potency of chemical fertilizers as agents in successful agriculture, when applied 

 to any soil deficient in the elements that such fertilizers can supply. 



Special Fertilizers! According to authentic sources, Prof. Johnston, of Scotland, 

 was the first to prescribe special fertilizers in detail for special crops, his general principle 

 being that the manui-e applied to the soil must contain all those inorganic or mineral sub 

 stances which the crop we wish to grow carries off the soil, and in the relative proportions in 

 which they are respectively found in the ash of the plant (the ashes remaining after burning 

 the entire plant), the exception being to omit from the application those elements already 

 abundant in the soil. He also favored the addition of organic matter to the soil, in the form 

 of animal or vegetable substances, in order to restore the elements of this nature that the 

 cultivated crops had extracted in their growth. 



Prof. Ville, of France, has based a theory of fertilizing upon the foil ov/ing propositions: 

 &quot; 1st. Give the earth more phosphates, more potash and lime, than the harvests have taken 

 from it. 2d. Give it fifty per cent, of the nitrogen they contain.&quot; He has also given various 

 recipes for complete fertilizers for special crops, based upon the above principles. Prof. 

 Stockbridge, of the Massachusetts Agricultural College, has arrived at the opinion, after 

 various and repeated experiments at the agricultural college farm, that the only substances 



