THE RELATIONS OF GEOLOGY TO AGRICULTURE. 



555 



commercial fertilizers by Prof. C. A. Goessmann, in the tenth annual 

 report to the Massachusetts Agricultural College, January, 1873. 



The first table shows the amount and kind of plant-food contained 

 in one thousand pounds of various air-dried substances. 



Stable manure is one of the most important fertilizers, yet its pecu- 

 liar value depends more on its influence upon the physical condition of 

 the soil than its chemical composition. The following statement will 

 show its chemical character in various stages of disintegration. One 

 thousand pounds contained (Wolff.), 



When fresh, 



When half decomposed, . . 

 When more decayed, . . . 



J2 

 D 



i-5 

 1.9 

 1.6 



The following analyses by Dr. Goessmann were made from samples 

 taken from the original packages in which they were placed for sale by 

 the manufacturers. As the farmer does not propose to pay for anything 

 but phosphoric acid, nitrogen (or ammonia), and potassa, the results are 

 given with particular reference to these substances. The valuation of 

 these articles has been made in conformity with the prices of late recog- 

 nized by dealers and consumers in our section of the country. These 

 prices are 16.25 cents for each pound of soluble phosphoric acid, 13.2 

 cents for every pound of reduced phosphoric acid, 6 cents for every 

 pound of insoluble phosphoric acid, 30 cents for each pound of nitro- 

 gen, and 8 cents for each pound of potassa. Reduced phosphoric acid 

 is that portion which has apparently once been rendered soluble in 

 water, but has become insoluble again in consequence of peculiar reac- 

 tions which sometimes occur in the manufactured fertilizer. Its com- 

 pound with lime is soluble in citrate of ammonia, and in a suitable condi- 

 tion for speedy absorption under the influence of the carbonic acid of 



the soil. 



I. 



Ammoniated Bone Superphosphate of Lime, manufactured by 



Russell & Co. 



Moisture and volatile matter, 61.54 per cent. 



