The Soil. 
55 
§ 116. The water-soluble in the soil and the incrustations 
formed upon the soil are very different in composition. 
§ 117. The incrustations are formed by the evaporation of 
water from the surface of the soil, which, owing to the deportment 
of the solutions of these salts toward capillary action, and the chemi¬ 
cal instability of the hydrated salts themselves, effects their separa¬ 
tion from the soil solutions. 
§ 118. The water-soluble in the soil is not identical with 
ground water solutions, probably due to reactions dependent upon 
the relative masses, which react upon each other within the soil and 
during the extraction. 
§ 119. The reactions near the surface of the soil are quite dif¬ 
ferent from those more remote. This is indicated by the solutions 
yielded by samples taken to depths of two and four inches. 
§ 120. There is, in the samples of soil examined, both free 
ammonia and ammoniacal salts, which we interpret as indicating 
unfavorable biological conditions, which view is materially strength¬ 
ened by the nitrates in the ground waters. 
§ 121. There is a significant gain in the total soil nitrogen 
during the time of the experiment, which may have been favored 
by, but was not dependent upon, the application of manure. 
§ 122. The nitrates in the first two inches of this soil are from 
nine times to two hundred times as great as in the second two 
inches, corrobative of the suggested reduction in certain zones of the 
soil. 
§ 123. Air dried soil samples can be kept for a year or more 
with ordinary precautions, without material change in their nitrogen 
content. 
§ 124. The humus in this soil is nearly as abundant as in 
average Eastern soils, and we were unable to find anything about 
it markedly different from ordinary humus. It is unlike the 
humus of arid soils, in that it is not so rich in nitrogen as they 
have been found to be. 
§ 125. The solutions of the humus carried relatively very 
large amounts of silicic acid, phosphoric acid, potash and lime. The 
precipitated humus did not carry much lime. 
§ 126. The effect of the cultivation, manuring, etc., for three 
seasons, may be summed up by stating that the store of plant 
food in the surface soil, taken to a depth of ten inches, was actually 
increased. This, however, was the lesser part of the improvement, 
the greater part lay in the betterment of the general conditions, 
whose best features cannot be shown by chemical analysis, or ex¬ 
pressed in any formula. 
