1899.] 



PUBLIC DOCUMENT — No. 33. 



131 



Summary of Yield of Crop (1890-94), 



Plats. 



1890. 



Potatoes. 



1891. 



Wheat. 



is»a. 



Serradella. 



1803. 



Corn. 



1894. 



Barley. 



Platl, 

 Plat 2, 

 Plat 3, 

 Plat 4, 

 Plat ft, 



1,600 

 1,41ft 

 1,500 

 1,830 

 2,120 



380 

 340 

 215 

 380 

 405 



4,070 

 3,410 

 2,750 

 3,110 

 2,920 



1,660 

 1,381 

 1,847 

 1,469 

 1,322 



490 

 40ft 

 290 

 460 

 390 



Phosphoric Arid applied to and removed from Field. 



[Pounds.] 



* None. 



Conclusions. 



From the previous statement of comparative yield we find 

 that the plat receiving dissolved bone-black leads in yield 

 during the first two years, while for the third, fourth and 

 fifth years the plats receiving insoluble phosphates are ahead, 

 phosphatic slag being first, South Carolina floats second and 

 Mona guano third. 



Description of Modes of Analysis adopted in our Investi- 

 gations of Samples ok Sou. taken from the Above-men- 

 tioned Five Plats in September, 1894, in the Manner 

 recommended by the committee of the american asso- 

 CIATION of Official Chemists, Prof. Harry Snyder of 

 Minnesota, Chairman. 



/. — Total Phosphoric Acid. 

 Ten grams of soil are digested with 100 c.c. of pure 

 hydrochloric acid, of specific gravity 1.115, for ten con- 



