584 



INDEX. 



nitrogen, 150 ; top - dressing with, 

 o44. 



Nitrates, amount lost by drainage, 

 140 ; amount produced at different 

 times, 189 ; amount in soil, 129 ; 

 conditions diminishing loss of, 139 ; 

 constantly formed in soil, 138 ; in 

 barley -soils, 158 ; in cropped soils, 

 130, 157 ; in drainage-waters, 160, 

 188 ; in fallow-soils, 129 ; in man- 

 ured wheat-soils, 131, 157 ; in soil, 

 129, 162 ; lost by drainage, 137 ; 

 most formed in summer, 139 ; 

 nitrogen as, in Rothamsted soils, 

 198 ; position of, in soil, 188 ; 

 quantity formed in fallow -fields, 

 188. 



Nitre, beds, 163 ; occurrence of, 162 ; 

 soils of India, 162. 



Nitric acid, amount of, supplied to 

 soil by rain, 155 ; derived from sea- 

 weed, 337 ; formed from ammonia, 

 118 ; formed from nitrous acid, 168 ; 

 in farmyard manure, 259 ; in soil, 

 128 ; lost in mixing manures, 536 ; 

 most important nitrogen compound 

 for plants, 161 ; relation of, to 

 plants, 50 ; source of, in nitrate 

 of soda, 337. 



Nitrification, 51, 52, 161-198 ; action 

 of gypsum on, 173 ; alkalinity 

 necessary for, 172 ; in asparagin, 

 182 ; bearing of, on agriculture, 

 193 ; in bones, 182 ; cause of, 165 ; 

 conditions favourable for, 170 ; 

 deuitrification, 177 - 179 ; effected 

 by micro-organisms, 51, 167 ; in 

 ethylamine, 182 ; in fallow-fields, 

 184 ; food - constituents necessary 

 for, 170 ; field experiments on rate 

 of, 187 ; in gelatin, 182 ; in horn, 

 182 ; laboratory experiments on 

 rate of, 185 ; in manures, 190, 192 ; 

 in milk albuminoids, 182 ; mineral 

 salts necessary for, 52 ; moisture 

 necessary for, 52, 176 ; old theories 

 on, 196 ; organic matter not neces- 

 ary for, 169, 196 ; oxygen necessary 

 for, 52, 173 ; plant-roots promote, 

 181 ; in rape-cake, 182 ; rate of, 

 183 ; rotation of crops, bearing of, 

 on, 195 ; soil best suited for, 192 ; 

 in subsoils, conditions favourable 

 for, 181 ; substances capable of, 181; 



in summer, 183 ; sunlight, effect 

 of, on, 176 ; temperature necessary 

 for, 52, 175 ; in thiocyanates, 182 ; 

 hi urea, 182 ; in wool, 182. 



Nitrifying organisms, depth found 

 at in soil, 180 ; distribution of, in 

 soil, 179 ; effect of poisons on, 176 ; 

 organic matter not required by, 169. 



Nitrobaeter, 167. 



Nitrogen, 115-160 ; absorbed by soil, 

 81, 131 ; accumulates in pastures, 

 134 ; in air, 116 ; as ammonia in 

 soils, 127 ; amount of, in plants, 

 40; amount of, in soil, 123; arti- 

 ficial supply of, 150 ; in bat guano, 

 325 ; in bones, 363, 364 ; combined, 

 in air, 118 ; combined, in rain, 119, 

 155 ; condition of, in manures, 540 ; 

 converted into nitrates in soil, 51 ; 

 in cow - dung, 226 - 228 ; in cow 

 excrements, 278 ; in cow - urine, 

 230 ; difference between surface and 

 subsoil, 126 ; different forms of, 45, 

 116 ; dissolved in rain, 131 ; in 

 dried blood, 424 ; in farmyard 

 manure, 260; in fish -guano, 321; 

 fixation of free, 136 ; forms of, in 

 plants, 491 ; free, relation of, to 

 plant, 117; gain of, with legumin- 

 ous crops, 135 ; in guanos, 329 ; 

 in hoofs and horns, 426 ; in horse- 

 dung, 226 - 228 ; in horse - man- 

 ure, 243 ; in horse - urine, 230 ; 

 importance of, in soil, 88 ; in lean 

 flesh, 424 ; in leather, 428 ; least 

 abundant of manurial ingredients 

 in soil, 271 ; loss of, artificial sources 

 of, 144 ; loss of, by crops, 144 ; 

 loss of, on farm, 146 ; loss of, 

 sources of, 137-150 ; loss of, total 

 amount of, 142 ; lost in the arts, 

 148; lost in free condition, 141; 

 lost in treating farmyard manure, 

 146; lost in milk, 147; lost by 

 retrogression, 142 ; in Manitoba 

 soils, 156 ; in meat - guano, 324 ; 

 nature of, in soil, 124 ; as nitrates 

 in soil, 128 ; as nitrates in cropped 

 soils, 130, 157 ; as nitrates in Eoth- 

 amsted soils, 198 ; as nitrates 

 in wheat - soils, 157 ; in nitrate of 

 soda, 343 ; nitric, in soil, 128 ; 

 organic, absorbed by plants, 47 ; 

 organic, in soil, 125 ; original 



