72 FERTILIZERS. 



tween the original engine and the after-product may be 

 more that of striking contrast than one of resemblance, 

 so, I believe, we farmers ought always to feel a debt of 

 gratitude to the professor for starting on the farm the 

 formula system of manuring, thus insuring it a future 

 outside of the laboratory. All manufacturers of formulas, 

 as far as I have observed, now take into consideration 

 what they have ascertained of the feeding-habits of plants. 

 Now, let each farmer who uses formulas, ascertain, by 

 actual trial, the peculiar needs of his own soil, and modify 

 the application of these formulas accordingly, and he will 

 certainly have something better in his hands than the 

 best superphosphate in the market. 



TESTING OUR SOILS. 



Professor Atwater was the first in this country, as far 

 as my knowledge extends, to digest into a practical plan 

 the idea of testing our soils to ascertain which of the three 

 elements is especially lacking. The test is -most satis- 

 factory on poor or worn-out soils. The fertilizers with 

 which to make these tests are put up seven in number, 

 making a full set, which is sold for seven dollars, the 

 bare cost. The sets are not sold in parts ; they contain 

 the elements singly and in combination. The quantity of 

 each lot is sufficient for one-tenth of an acre, making fer- 

 tilizing material sufficient for seven-tenths in all. Corn, 

 potatoes, or any other crop, may be planted, leaving two 

 of the plots without any manure, on the remaining tenth 

 using the same value of barn manure. The design of these 

 experiments is, to enable farmers to settle the question in 

 which of the three elements, viz., nitrogen, potash, or 

 phosphoric acid, the soil is especially deficient, and which 

 combination of them is most needed to produce the crop. 

 Besides the set to settle these questions, others are put up 



