TABLE OF CONTENTS 
Section. 
1. Scope of bulletin. 
2. Choice of plot. 
3. Extension of object. 
4. Gypsum not advantageous. 
5. Character of soil. 
6. Drainage. 
7. Formerly bed of stream. 
8. Origin of soil. 
9. Source of the alkali. 
10. Incrustations and well waters contain the 
same salts. 
11. Soil largely feldspathic. 
12. Potash in feldspar available to plants. 
13. Importance to agriculture. 
14. Decomposition of feldspar. 
15. The hydrous silicates. 
16. Source of salts not distinguishable. 
17. Salt contents changing. 
18-19-20. Limitations of study. 
21. Preparation of samples. 
22-28. Physical analysis, A to F. 
29. The chemical analysis of fine earth. 
30. Mineralogical character and source of the 
fine earth particles. 
31. Mechanical analysis of sandstone. 
32. Statement generally applicable. 
33. Our soil derived from granites of the Colo¬ 
rado range. 
34. Loessial soils, Weld county. 
35. Ratio of quartz to feldspar in the loess. 
36. Proportion of small sand particles. 
37. Similarity of composition does not exclude 
differences in properties. 
38. Analysis of mechanical division of soil A. 
39. Probable courses of changes in composi¬ 
tion of soil mass. 
40. Fine particles of dust probably precipi¬ 
tated. 
41. Analysis of particles of fine earth show no 
definite ratios. 
42. Solvent action of hydrochloric acid. 
43. Chemical analysis not competent criteria. 
44. The samples analyzed. 
45. The amount of water received. 
46. The rate at which the water plane fell. 
47. The deportment of soil toward water. 
48. Experiments to determine the rate at 
which soil dries, and the amount of 
shrinkage. 
49. Analysis of hydrochloric solutions in soil. 
50. Consideration of analytical results. 
51. Cultivation does not eliminate alkali. 
52. Movement of alkali in the soil. 
53. Gain in organic matter. 
54. Improvement in soils not shown by the 
analysis. 
55. Some results due to feldspar. 
56. Solvent action of dilute acids on feldspar. 
57-60. Action of water and carbonic acid on 
feldspar. 
61. Experiments with oats. 
62. Composition of feldspar used. 
63. Amount of nitrogen in oat hay, analysis of 
ash. 
64. Finely powdered feldspar a part of soil. 
LIST OF 
No. 
1 . Mechanical Analyses of Fine Earth. 
2 . Mass Analyses of Several Soils. 
3. Rates of Loss of Water from Soil. 
4. Analyses of Soils. 
5. Analysis of Oat Ash Grown with Feldspar. 
6 . Analysis of the Water-Soluble in Sample B. 
7. Analysis of Water-Soluble, Soil A, First 
Two Inches 
8 . Analysis of Water-Soluble, Soil A, Second 
Two Inches. 
9. Analysis of Water-Soluble, Soil B, First 
Two Inches. 
10. Analysis of Water-Soluble, Soil B, Second 
Two Inches. 
11. Analysis of Water-Soluble, Soil C, First 
Two Inches. 
Section. 
65. Importance of feldspar in our soil. 
66-67. Action of hydrochloric acid greater on 
the soil than on fresh feldspar. 
68. Percentage of water-soluble in the soil 
samples. 
69. The order followed in combining the re¬ 
sults of the analysis. 
70. Analysis of water-soluble. 
71. What the analyses shows. 
72. The water-soluble portion of the soil dif¬ 
ferent from the incrustation. 
73. Gypsum abundant in the soil. 
74. Salts in the ground water more similar to 
the water-soluble in the soil than to the 
alkali which effloresces. 
75. Silicic acid more abundant in water- 
soluble portion of the soil than in the 
ground waters. 
76. Analysis of water-soluble portion of the 
first two inches of soils A, B, C and D. 
77. The long duration of the washing and the 
large quantity of water used make no 
difference in the result. 
78. Distribution of the salts in the first and 
second two inches of the soil. 
79. Presence of phosphoric acid in drainage 
waters usually in very small quantities. 
80. The alkali. 
81. Character of alkali deposits vary. Analysis 
of alkali from soil A. 
£2. Formation of alkali incrustations ex¬ 
plained. 
83. Alkalinity of samples of soil. 
84. Free ammonia in the soil. 
85. Quantity of ammonia in dry soil. 
88. Ground waters show ammonia and nitrites. 
87. Volatile acids in the soil. 
88. Nitrogen and nitrites in the soil. 
89-91. Effect of cultivation on the amount of 
nitrogen in the soil. 
92. Nitrates in the first and second two inches 
of soil. 
93. First two inches of soil analyzed richer in 
nitrates than the second two inches. 
94. Do soil samples, when kept, absorb nitro¬ 
gen ? 
95. Humus in the soil normal in quantity and 
composition. 
96. Composition of precipitated humus. 
97. Humus as a solvent. 
98. Ash in ammoniacal solution of humus. 
99. Value of humus as a plaut food. 
100. Some results of the work of three seasons. 
101. Analysis of samples taken at beginning of 
experiment summarized. 
102. Phosphoric acid more abundant in the 
samples taken in the fall than in those 
taken in the spring. 
103. Analysis taken at conclusion of experiment. 
104. Humus contained 40 per cent, of the total 
amount of nitrogen in the soil. 
105. The improvement in the soil much greater 
than is indicated by chemical analysis. 
106-107. Analysis of some Colorado soils. 
108-126. Summary. 
TABLES. 
No. 
12 . Analysis of Water-Soluble, Soil C, Second 
Two Inches. 
13. Analysis of Water-Soluble, Soil D, First 
Two Inches. 
14. Analysis of Water-Soluble, Soil D, Second 
Two Inches. 
15. Analysis of Alkali, Soil A, June 23, 1897. 
16. Analysis of Soil A, July 5, 1897. 
17. Total Nitrogen in the Soil. 
18 . Nitrates in the Soil. 
19. Elementary Analysis of Precipitation. 
20 . Analysis of Soil at the Beginning of Experi¬ 
ment. 
21 . Analysis of Samples of Soil Taken in 1899. 
22 . Analysis of Some Colorado Soils. 
