704 



STATE BOARD OF AGRICULTURE. 



water niilil ils iiioislure' content wiis vediir-ed lo nlxmt tlie oi)tin)niii point. 

 The soil then was placed in a glass tnmbler, thoroughly stirred, weighed 

 and water was added to -it as often as it was deemed necessary in 

 order to keep it at tlie optimnm moisture content. In order to simulate 

 further field conditions the soil was kept outdoors most of the time. At 

 llie end of 10, 80, and GO days a small composite sanqde was taken, air- 

 dried, and its freezing point depression determined as before. By deter- 

 mining the lowering of the freezing at the beginning and at the end of 

 10, 30, and 00 days, tlie rate and extent of solubility could thereby be 

 ascertained. Also ]»y using fresh soils and not dislurbing thein when 

 wet their physical coiidilion remained excellent and very much as under 

 field conditions. 



It is readily realized that under these favorable field conditions nitri- 

 fication is very apt to take place in the soils and consequently an error 

 may be introduced in the method of measuring the rate and extent of 

 solubility of soils. While some nitrification undoubtedly took place in 

 the soils yet the error introduced, as is revealed by the results, is prac- 

 tically negligible. 



The data obtained in this phase of the investigation are presented in 

 tables 13 to 16 inclusive. For purpose of convenience and immediate 

 reference the fertilizer treatment of the soils is again given and is placed 

 at the bottom of each respective table. 



TABLE 13.— RATE AND EXTENT OP SOLUBILITY OP RHODE ISLAND SOILS AT 

 OPTIMUM MOISTURE CONTENT, KEPT MOSTLY OUTDOORS. FIGURES REPRE- 

 SEN FREEZING POINT DBPR'ESSION. 



1.58 pouiuls nitrate of soda, 90 iiouiuls sulfate of ammonia, 4.50 pounds tankage, 



571 pounds acid phosphate, 07 pounds sulfate of potash, lime. 

 127 pounds nitrate of soda, '574 pounds acid phosphate, 200 pounds salt, 856 



pounds wood ashes, lime. 

 127 pounds nitrate of soda, 9fi pounds sulfate of ammonia. 753 pounds tankage, 



659 pounds acid phosphate, 200 pounds salt, 1484 pounds wood ashes, lime. 

 191 pounds nitrate of soda, 144 pounds sulfate of ammonia, 301 pounds tankage, 



444 pounds double superphosjihate, 131 pounds magnesium sulfate, l03 



pounds sulfate of potash, lime. 

 Same as No. 4 without lime. 

 No fertilizers, almost a virgin soil. 

 Virgin soil. 



