120 



These observations show a large absorption of ammonia in 

 whatever form it enters the solution, but it must also be said 

 that even the weakest solution, 160 parts per million, is con- 

 centrated, when compared with normal soil solutions. The 

 strongest solutions used contained 3400 parts per million. The 

 largest absorption shown by the table is 3294 parts per million 

 of the soil, while the smallest is 229 parts. 



Kullenberg tried recovering the ammonia again, by percolat- 

 ing distilled water through the soil placed in a funnel. He 

 digested during 24 hours 100 grams of this soil with 250 c. c. 

 of an ammonium phosphate solution, which contained .7260 

 grams of phosphoric acid and .2911 grams of ammonia; then 

 added enough water to obtain a filtrate of '250 c. c., repeating the 

 addition of water, with the results as given in the next table. 



Amounts of phosphoric acid and ammonia washed away from soil 

 with distilled water. 



Enough has been cited to show the tendency to absorption 

 from a solution of ammonia. by soils when the solutions are 

 strong. 



ABSORPTION OF POTASH BY SOILS. 



OBSERVATIONS OF VOELCKER.* 



There have been brought together here in tabular form, with 

 additional data, the results of a considerable number of the 

 absorption experiments of Yoelcker, without commenting on his 

 mode of procedure more than is indicated by the table, as it was 



'Journal Royal Agricultural Society, Volume XXI, 1860, p. 105. 



