The Soil. 
31 
took from the feldspar 1.4417 grams of potash. The potash added 
in the seed has been deducted. The silicic acid appropriated by the 
plant indicates the decomposition of the silicate. The partially de¬ 
composed, finely comminuted feldspar is actually a part of the soil. 
Its deportment toward water, especially when charged with carbonic 
oxid, is also strongly suggestive of this conclusion. 
§ 65. This fact is of very general importance, as it applies to 
so large a portion of our soils; it also facilitates the interpretation of 
our analytical data, and enhances their value a little. The mass 
analyses show that our soils contain from 2.24 to 2.50 per cent, of 
potash—the latter seems to be the rule, about 2.50 per cent. The 
agricultural analysis of samples from all parts of the State show a 
range from 0.10 to 1.50 per cent. In fifty-eight analyses of samples 
from different counties of the State, only five fall so low as 0.15, and 
very few of the rest so low as 0.25 per cent. It is evident that, so 
far as the results of analyses are reliable, the soil with which we 
have been experimenting is richer in this constituent than the aver¬ 
age soil. This is, I believe, true of all of alkali land. 
ANALYSIS OF THE ACID SOLUBLE AND INSOLUBLE PORTION OF SOIL A. 
§ 66. The mineralogical composition of our soil, i. e., quartz 
and feldspar, and the decomposition products of the latter, together 
with the results of our experiments with feldspar, suggest the combi¬ 
nation of the mass analysis and agricultural analysis to give us 
some idea of the relation of the agricultural analysis to the actual 
composition of the soil. We, therefore, in order to exhibit as fully 
as we can the chemical composition of this soil, give the agricultural 
analysis of soil A, together with the analysis of the residue desig¬ 
nated as insoluble in the agricultural analysis. 
TABLE VII.—ANALYSES OP THE ACID SOLUBLE AND INSOLUBLE 
PORTION OF SOIL A. 
Soluble in HCl., sp. gr. Insoluble in HCl., sp. gr. 
1.115,5 days digestion. 1.115,5 days digestion. 
Per cent. Per cent. 
Silicic Acid.17.875 46.870 
Sulfuric Acid. 0.827 None 
Carbonic Acid. 1.208 . 
Chlorin. 0.014 . 
Phosphoric Acid. 0.112 None 
Potash. 1.495 0.800 
Soda. 0.624 0.560 
Lime. 2.479 0.310 
Magnesia. 1.649 0.170 
Ferric Oxid. 4.075 0.400 
Aluminic Oxid. 7.387 4.330 
Manganic Oxid. 0.200 Trace 
Moisture at 100° C. 3.296 . 
Ignition. 5.402 . 
46.640 53.440 
Total 
100.080 
