250 



INDEX 



Sulphuric acid as plant poison, 234 



Sunflower seed, 136 



Sunrise rays, 83 



Sunshine, effect of, on plants, 83 



Superphosphates, 112 



Surface pressure, 49 



Swedes, 143 



Sweet corn, 127 



potatoes, 146 

 Symbols, chemical, 3 



Tares, 149 



Taurocholic acid, 160 



Temperature, absolute zero of, 26 

 effect of, on gases, 26 

 effect of, on plants, 82 

 of maximum density of water, 

 73 



Tendons, 158 



Thermal value of foods, 173 



Thermometric scales, 237 



Tobacco as insecticide, 231 



Transpiration from leaves, 81 



Trefoil, 149 



Trypsin, 160 



Turnips, 143 



Twaddle's hydrometer, 237 



Urea, 162 



Uric acid, 162 

 Urine, 162 



Valency, lO 



Valuation of foods, 178 

 of manures, 115 



Values *' per unit " of manurea, 



117 

 Vetches, 149 



Voet-gangers (hopping locusts),223 

 Volatile, 10 



Warp soils, 69 



Water, action of, on lead, 65 



action of, on rocks, 38 



hard, 64 



mineral, 63 



motion of, in soil, 49 



natural, 62 



organic matter in, 66 



physical properties of, 71 



rain, 62 



required by animals, 178 



river, 67 



soft, 65 



soil-, 57 



spring, 63 



typical good and bad, 66 

 Waxes, 90 

 Weather-glass, 26 

 Weevils, destruction of, 231 

 Wheat, 120 * 



Whey, 210 



White ants, destruction of, 222 

 Wind, action of, on rocks, 38 

 Wolff's feeding standards, 175 

 Woollen waste, 104 

 Worms, in soil formation, 40 



Xanthine, 157 

 Xenon, in the air, 28 



PRINTED AT THE COMPI,ETE PRESS 



WEST NORWOOD 



I^ONDON 



