296 



INDEX 



Pancreatic juice, 171, 172, 173 



Papain, 16 



Pastures, fattening, 195 ; manures 



for, 265 

 Peas as food, 182 

 Peat, 130 ; moss litter, 228 ; moss 



manure, 236; soils, 86, 90, 95, 



123, 153, Its 



Pectins, 71, 75, 182 



Pepsin, 16, 173 



Peptone, 124, 173 



Percolation, 105 



Pericarp, 64 



Peruvian guanos, 257 



Phosphate of lime, as a food con- 

 stituent, 175 



Phosphoric acid, necessary to plant 

 growth, 50 ; in soils, 94, 149 ; 

 removed in four-course rotation, 

 159; deficient in clays, 167; in 

 fertilisers, 254 



Physical effects of farmyard manure, 

 241 



Pigs, composition of, 207 



Plant, food, migration and storage 

 of, 60, 63 ; food, dormant and 

 available in soil, 151 ; excretions, 



157 

 Ploughing, autumn, 107 ; spring, 



108 ; work done by horses in, 200 

 Pore space, 104 

 Potash, in plants, 50, 53 ; in soils, 



94, 149 ; removed in four-course 



rotation, 158 ; abundant in clays, 



167 ; manures, 257 

 Potato, 72; districts, early, 118; 



composition of, 182 ; manures for, 



257 



Prairie soils, 144 



Preservatives in dung-heaps, 233 



Protease, 16 



Protein, in plants, 6 ; and dz-proteins, 

 66, 70, 71, 177 ; breakdown and 

 reconstruction, 125 ; in foods, 

 169 ; digestion of, 173 ; in silage, 



177 ; heat value of, 188, 201 ; in 

 terms of carbohydrates, 183 ; fuel 

 value of, 187 ; requirements, 174, 

 201 



Protozoa, 147 



Puddled clay, 91 



Putrefaction, 124 



Quality in produce, *j*i 

 Quartz, 80 



Rape, cake, 178 ; dust, 259 



Rations, construction of food, 217 ; 

 for milch cows, 281 



Rennet, 272, 285 



Respiration, in plants, 29, 60, 63 ; 

 of roots, 47 ; during storage of 

 root crops, 71 ; chamber, 211 



Ripening, of grain, 66 ; of fruits, 

 57 



Rock, 78 ; primitive, 80 ; volcanic, 

 80 ; phosphate, 255 



Rolling, no 



Root, 22 ; hairs, 43 ; adventitious, 

 44 ; source of water supply to 

 plants, 46 ; effect of frost on, 47 ; 

 absorbs soluble substances, 48 ; 

 etching action of, 49 ; part played 

 in weathering, 81 ; nodules, 132 



Root crops during storage, changes 

 in, 71 ; digestibility of, 178 ; com- 

 position of, 182 



Rotations, value of, I $6 



Ruminants, 172, 174, 177 



Sainfoin, 138, 168 



Saliva, 172 



Salt as a food constituent, 175 



Sand, deposition of, 82, 83 ; in 

 mechanical analysis, 88 ; pro- 

 perties of, 91 ; in foods, 170 



Sandy soils, 98, 107, 1 63 



Sap, 50 ; acidity, 49 



Sea, temperature in proximity to, 

 118 



