72 Journal of Agricultural Research voi.xv.no. 2 



The two soils are practically alike in their proportions of the mechanical 

 components. The observed difference in the apparent specific gravity 

 of the soils is probably the consequence chiefly of some unlikeness in 

 the arrangement of the constituent soil grains. 



THE CLAYS 



The characters of the separated "clays" were distinctly claylike. 

 When moist, they had a putty-like consistence; and, when dried, were 

 hard and broke with a gluelike fracture. Microscopic examinations of 

 the suspensions before the final sedimentation showed that most of the 

 particles, visible under a one-twelfth objective, had diameters less than 

 0.0025 mm. 



Portions of the clays were analyzed by the J. Lawrence Smith method, 

 with these results, in terms of the amounts of clay : 



Percentage 



of total potash 



in clays. 



Plot I , untreated 3- 3 10 



Plot 4, dressed with potash 3. 137 



The clay from plot 4, as with the entire fine soil, contained less potash 

 than the corresponding fraction of the plot i fine soil. In each case, 

 however, the clay contained a less percentage of potash than appeared 

 in the total fine soil. 



THE NONCLAYS 



The total potash in the washed nonclays was not determined directly. 

 Computed by difference, the percentages are, in terms of the amounts 

 of nonclays : 



Percentage 



of potash in 



nonclays. 



Plot I, untreated 4. 027 



Plot 4, dressed with potash 3. 701 



SOtUBIUTlES OP THE POTASH OF THE WASHED CLAYS AND NONCLAYS IN N/j AMMONIUM- 



CHLORID SOLUTION 



The washed clays and nonclays thus separated and air-dried were 

 treated in 50-gm. portions with 500 cc. of N/j ammonium-chlorid solu- 

 tion for five hours at 40° C, with hourly shaking, and the resultant 

 solutions were immediately filtered off and analyzed for potash. The 

 results are stated below in terms of the total weight of clays and nonclays, 

 respectively : 



Plot I, Plot 4, 



Potash dissolved from — per cent. ppr cent. 



Clay, washed o. 0352 o. 0408 



Nonclay, washed 0041 . 0050 



