xut 



Mica slate 119 



Minerals 106, 108 



" hydratiouof. 127 



" solution of 197 



" variable composition of. ...110 

 Moisture, effect of, on temperature 



of soil 193 



Mold 156 



Moor-bedpan 157 



Muck 155 



Nitrate of ammonia 71, 73 



" " " in atmosphere. 89 



Nitrates 253 



" as food for plants. 271 



" formed in soil 171, 179 



" in water 270 



" loss of. 270 



" reduction of 73, 82, 85 



" " "in soil 268 



" tests for 75 



Nitric acid 70 



" " as plant-food 90,98 



" " deportment towards the 



soil ,357 



" " in atmosphere 86 



" " " rain-water .. 86 



" " " soil... 251, 254 



" " " " sources of 256 



Nitric oxide 72 



Nitric peroxide 72 



Nitrification 252, 286 



" conditions of 265, 292 



Kitrogen, atmospheric supply to 



plants 95 



" combined, in decay. 291, 293 



" " of the soil... 275 



" combined, of the soil, 



available 283 



" combined, of the soil, 



inert 278 



" combined, of the soil, 



quantity needed for crops. 288 

 " free, absorbed by soil. . .167 



" " assimilated by the 



soil 259 



** " in soil 218 



" " not absorbed by 



vegetati on 26, 99 



" " not emitted by liv- 

 ing plants 23 



Nitrogen-compounds, formation of, 



in atmosphere. 75, 77, 83 



Nitrogenous fertilizers, effect on 



cereals... fi3 

 Nitrogenous organic matters of soil.274 



Nitrous acid 73 



Nitrous oxide 71, 93 



Ocher 156 



Oxidation, aided by porous bodies. 



169, 170 



Oxide of iron, a carrier of oxj'gen . . 257 



" " hydrated, in the soil.SoO 



Oxj'gen, absorbed by plants 98 



" essential to growth 23 



" exhaled by foliage 25,99 



" function of, in growth fU 



" in soil 218 



" supply 94 



" weathering action of 131 



Ozone 63 



" concerned in oxidation of ni- 

 trogen 82 



" formed by chemical action. 66, 67 

 " produced by vegetation. 67, 84, 99 

 " relations of, to vegetable nu- 

 trition 70 



Pan, composition of 352 



Parasitic plants, nourishment of. . .235 



Peat 155,224 



" nitrogen of 274 



Phosphate of lime 116 



Phosphoric acid fixed by the soil . . ..357 

 " " presence in soil 



water 315 



Phosphorite 116 



Plant-food, concentration of. 320 



" maintenance of supply. 371 



Platinized charcoal 170 



Platinum sponge, condenses oxygenl70 



Porphyry 120 



Potash, quantity in barley crop 363 



Provence, drouths of 198 



Pyrites 115 



Pyroxene 112 



Pumice 120 



Putrefaction 290 



Quartz ... 108,123 



Rain-water, ammonia in 60, 88 



'• nitric acid in 86 



" phosphoric acid in 94 



Ree Ree bottom, soil of 160 



Respiration of the plant 43 



Rocks 106. 117 



" attacked by pjiute 140 



