350 



INDEX 



Parsnips, manure for, 199 



Particles of soil, 50 



Pasteur's experiments, 141 



Pasture soils, nitrogen in, 14 



Patagonian guano, 296 



Pearl ash, 27 S 



Peas, manures for, 199, 288 



Pea straw, 313 



Peat, 37, 324 



Peat litter, 313 



Perchlorates in nitrate of soda, 



263 



Percolation, 66, 68 

 Peruvian guano, 295 

 Phosphate, aluminium, 133, 220 

 basic, 229 



,, dicalcic, 215 



ferric, 133, 220 



,, monocalcic, 215 



,, tetracalcic, 229 



,, tricalcic, 215 



,, reverted, 219 



Wiborgh, 235 

 Phosphates, native, 206 



,, in soils, 133 



Phosphatic guanos, 214, 295 



,, manures, 206 



Phospho-nitrogenous manures, 



237 

 Phosphoric acid, 59, 216 



,, in crops, 169 



,, ,, manures, 180. See 



also Various 

 manures. 



,, ,, plants, 6 



,, ,, soils, 122 



,, retention of, 105 



Phosphorite, 209 

 Physical constituents of soils, 2 

 ,, properties of soils, 50 

 Pig-iron, 224 

 Pigs' dung, 306 



Pipe-clay, 59 

 Plant food, 1, 3, 5, 7 



,, ,, amount required by 



crops, 168 



,, ,, available, 123 

 ,, ,, retained by animals, 



167, 309 



Plants, analysis of, 4 

 ,, ash of, 6 



,, essential constituents, 8 

 Plastic clay, 33, 87 

 Plutonic rocks, 2!) 

 Polyhalite, 280, 2S2 

 Portugese phosphate, 210 

 Potash in drainage, 99 



manures, ISO, 283. ,S'ee 

 also Various manures. 

 ,, ,, plants, 6 

 ,, ,, rocks, 30 

 ,, soil, 122, 285 

 ,, liberation of, 130 



minerals, 277 

 ,, retention of, 105 

 salts, 279 



Potash manures, crops which 



require, 285 



,, ,, soils suitable 



for, 285 

 Potashes, 27s 

 Potassium cyanide, 13 

 nitrate, 269 



Potatoes, composition of, 169, 194 

 ,, manures for, 196, 199, 

 288 



Precipitated phosphate, 235 

 Principles of manuring, 178 

 Produce, loss by sale of, 171 

 Productiveness, natural, 163 

 Proteids, conversion to ammonia, 



154 



Pumpkins, manure for, 199 

 Putrefaction, 151 



