12 Liquid Manure. 



2. Like the preceding soil the pasture land yielded to liquid 

 manure some additional organic matter. This organic matter 

 likewise contained some nitrogen. 



3. The filtered liquid contained nearly 21 grains more of 

 mineral matter than the manure before coming in contact with 

 soil. 



4. This increase in mineral matter is chiefly due to carbonate 

 of lime, which is much more abundant in the filtered liquid than 

 in the original liquid manure. 



It is chiefly in the state of bi-carbonate that lime occurs in the 

 manure ; only a small proportion occurs as sulphate of lime or 

 gypsum. 



If the sulphuric acid in these analyses is united with lime to 

 form gypsum, and the rest of the lime calculated as bi-carbonate 

 of lime, there will be in the liquid manure 



Before After 



Filtration. Filtration. 



Sulphate of lime 6'69 4-64 



Bi-carbonate of lime 22-45 59-91 



It will be seen that the proportion of bi-carbonate of lime 

 which passed into the liquid manure is greater than in the pre- 

 ceding experiment, notwithstanding the much larger quantity of 

 carbonate of lime in the Cirencester soil. We have here an 

 indication that the changes which take place when manuring 

 matters are brought into contact with soil are not merely depen- 

 dent on the percentage composition of the soil, but likewise on the 

 state of combination in which the constituents occur in the soil. 

 A soil containing much less lime may thus yield to a liquid 

 containing a number of organic and inorganic compounds even 

 more lime than another soil three or four times as rich in car- 

 bonate of lime. 



5. The proportion of chloride of sodium (common salt) in the 

 filtered liquid is nearly as large as in the original liquid. 



6. On the other hand the absorption of potash is very marked. 

 Originally the manure contained 16'92 of potash and 2'87 of 

 chloride of potassium per gallon. After having been left in 

 contact with soil it only contained 5*19 grains of potash and 4'S8 

 grains of chloride of potassium. Calculating the potassium in 

 chloride of potassium as potash, and adding it to the rest, we 

 have 



Grains of 

 Potash. 



In manure before filtration 18' 65 



after filtration.. 8 '26 



Difference 10'39 



20,000 grains of soil in this experiment thus absorbed 10'39 

 ains of potash, or 1000 grains absorbed '519 grains of potash. 



