252 



INDEX 



up, 98 ; target reading, 

 100; to determine the 

 height, 99; using, 98; 

 using cheaper levels, 104 ; 

 water level, 106. 



Leveling, 94, 95 ; cautions, 102 ; 

 computations, 102, 122, 

 123 ; convenient aids, 

 118; direct reading, 100 ; 

 for drains, 115; for 

 laterals, 146 ; in detail, 

 123; keeping notes, 102, 

 117; moving and re- 

 setting, 103 ; records, 102, 

 117; target reading, 100; 

 with cheaper levels, 119; 

 with high-grade level, 

 120 ; with hose-level, 173. 



Leveling rods, 97. 



Leveling rods for hose-level, 170; 

 construction, 170; long 

 rod, 171 ; short rod, 171 ; 

 zero mark on, 170. 



Limitations of hose-level, 166. 



Location of outlet, 80. 



Location of silt- basin, 90, 91. 



Location of upper ends of mains and 

 laterals, 114. 



Long stakes for use with hose- 

 level, 180. 



Lowering of ground water-table, 

 200, 206; bound to be 

 remedied, 207 ; case not 

 serious, 206 ; experience 

 in other countries, 207 ; 

 remediable, 207. 



McGee, W J, 200. 



Mains, 76 ; adjusting to needs, 

 88 ; grade of, 88 ; chang- 

 ing, 88 ; range of grade, 

 88 ; relation of size to 

 grade, 88. 



Making close joints, 142. 



Making computations, 102, 122, 

 123. 



Making openings in tile, 150. 



Marine marshes, 61 ; extent, 61 ; 

 how formed, 61 ; value, 61. 



Maximum acre capacity of tile, 86. 



Meaning of lowering of ground 



water-table, in terms of 



rainfall, 206. 



Methods of drainage, 70. 

 Michigan Agricultural College farm, 



158. 



Michigan Experiment Station, 14. 

 Michigan system, 65. 

 Miller, N. H., 5. 

 Minnesota system, 65. 

 Mississippi delta, 60. 

 Missouri valley floods, 209. 

 Molds, 57. 



Moving and resetting level, 103. 

 Muck soils shrink after being 



drained, 158. 

 Musselman, H. H., 72. 



Nailing grade bars in place, 137. 



Nebraska, 12. 



Need for drainage indicated, 69. 



Negative readings with hose-level, 

 175. 



New Orleans, 62. 



Nitrification, 6 ; modified by tem- 

 perature, 6. 



Nitrogen, ammonia in the soil, 5 ; 

 forms in the soil, 5 ; nitric 

 nitrogen, 5; preparation, 5. 



Nitrogen fixation, 6 ; accomplished 

 by bacteria, 6 ; accom- 

 plished by molds, 6 ; on 

 roots of legumes, 6. 



Notes, 102, 117. 



Oath administered in some states 

 in receiving controversial 

 evidence regarding drain- 

 age matters, 220. 



Ohio, average yields of wheat, 204. 



Open ditch, 62, 70. 



Opening the ditch, 138 ; using line 

 for, 138. 



Optimism, 207. 



Ordering tile, 114. 



Order of steps in installing a tile 

 system, 163. 



Organizations of drainage district 

 must be authorized, 220, 

 223. 



