112 On the Chemical Properties of Soils. 
portion of the clear solution was then drawn off, and the ammonia 
contained in it determined in precisely the same manner as in 
the preceding experiment. 
Ammonia. 
Grains. 
Before contact with soil the solution contained in 
1000 grains -332 
After contact '115 
Difference -217 
Thus we see that 217 grains were removed from each 1000 
grains of liquid, or 3"038 grains from the whole litjuid, and re- 
tained by 3500 grains of soil. 1000 grains of soil therefore 
absorbed "868 of ammonia. By distillation the amount of am- 
monia in the liquid after contact with soil was found to be "131 
grains, in 1000 grains of liquid, or 2'814 grains from the whole 
liquid. Accordingly 1000 grains of soil absorbed "804 grains 
of ammonia. 
Third Experiment, on Stiff Clay Land. 
Tlie mechanical and chemical analysis of the soil and its subsoil 
furnished the following results : — 
Mechanical Analysis. 
Subsoil. Surface soil. 
Moisture 9-46 3-91 
Organic matter and water of combination . . 4'87 4*80 
Sand 9-26 10-97 
Lime 1-12 2-19 
Clay 75-29 78-13 
100-00 100-00 
Chemical Analysis. 
Subsoil. Surface soil. 
Moisture 9-46 3-91 
Organic matter and water of combination . . 4.87 4-80 
Oxides of iron and alumina 17-38 7-85 
Phosphoric acid -06 -04 
Carbonate of lime 1-02 2-08 
Sulphate of lime -13 "15 
Magnesia -92 J .^g 
Alkalies and loss -45) 
Insoluble siliceous matter (chiefly ck} ) .. C5-71 80-85 
100-00 100-00 
Equal parts of soil and subsoil were mixed together, and 3500 
grains of the mixture shaken up with 14,000 grains of ammonia 
solution, and treated as before mentioned : — 
Ammonia. 
Grains. 
Before contact with soil the solution contained in 
1000 grains -332 
After contact '143 
•189 
