Oct. 14. 1918 Fertilizer Potash Residues in Hagerstown Silty Loam 'ji 

 The net results of the separations were: 



Group. 



Clay, air-dry 



Nonclay, air-dr>^ 



Solution and mechanical losses 



Total 



Plot I . untreated. 



Weight. I Per cent. 



70 

 19 



II. 67 



85-17 

 3. 16 



600 



Plot 4, potash-dressed. 



Weight. 



Gm. 



66 



517 



17 



600 



Per cent. 



II. 00 



86. 17 



2. S3 



For a check upon the accuracy of the foregoing results obtained by 

 the separatory treatment of relatively large quantities of soil, mechanical 

 analyses of grand composites of the series composites for the respective 

 plots were made by Mr. Walter Thomas, of this laboratory, using the 

 Bureau of Soils methods and types of apparatus, upon 6-gm. portions 

 of the fine soils. His results were: 



Fine gravel . . . 

 Coarse sand . . . . 

 Medium sand. . 



Fine sand 



Very fine sand. 



Silt 



Clay 



Ignition loss . . 



Group. 



Diameters. 



Millimeters. 

 -I 



5 - -25 

 25 - .1 

 I - .05 

 05 - . 005 

 005- . O 



Plot I. 



Per cent. 

 16 



99.99 



Per cent. 



■33 



2.81 



2. 90 



.70 



14. 05 



63.46 



10. 24 



6.06 



100. 55 



These percentages differ somewhat from those reported earlier by 

 Brown and Skinner (/, p. 30) for the surface soils of these plots, who found 

 in brief: 



That is, they found less sand and more silt and clay, although their 

 disregard of ignition losses somewhat increased their percentages. 



In general, the figures obtained by the sedimentation of 6oo-gm. 

 portions of the soil are essentially confirmed by the mechanical analyses. 



