112 



INDEX 



Paterson, J. W., 17 



Pfeiffer, 47 



Phleum pratense, 50, 51, 56, 57 



Phosphates 



action of, on heavy clay soils, 89 et seq. 

 effect of, on accumulation of nitrates 

 in soil, 77 et seq.; on accumulation 

 of nitrogen in soil, 75; on herbage, 

 49 et seq.; on soil bacteria, 86; on 

 soil moisture, 63 et seq. ; on soil tem- 

 perature, 68 et seq. ; on soil texture, 

 73 et seq. ; on yield of hay, 22 et seq. ; 

 of fine grinding on availability of, 

 32; of rainfall on availability of, 46; 

 of sour soils on availability of, 47 



Poa trivialis, 50, 56, 57 



Potash, influence of, on yield of hay, 97 



PotentiUa reptans, 36 



Prunella mdgaris, 36 



Rainfall, effect of, on availability of 

 rock phosphates, 46; on perma- 

 nency of clover, 60; on yield of hay, 

 89 et seq. 

 Ranunculus, 24, 36 

 Rock phosphates 

 Algerian, which see 

 American, 8, 16 

 composition of, 9, 21 

 deposits of, 8 

 Egyptian, which see 

 field experiments with, in America, 11 ; 

 in France, 14; in England, 14; in 

 Scotland, 16; in Wales, 16; in Essex, 

 18 et seq. 

 Florida pebble, which see; soft, which 



see 



Gaf sa, which see 

 Nauru, 8 



North African, 8, 33, 42, 48 

 Ocean Island, 8 

 Tunisian, which see 

 Rothamsted, 75 

 Rumex acetosa, 24 

 Russell, E. J., 16, 36, 85, 86 



Saussure, de, 1 



Sillars, D., 2, 6 



Soil 



analyses of, at experimental centres, 19 

 bacteria, effect of phosphates on, 86 

 moisture effect of phosphates on, 63 



et seq. 



sourness, effect of phosphates on, 99 

 sourness, effect of, on clover plant, 60 



61 

 temperature, effect of phosphates on, 



68 et seq. 

 texture, effect of phosphates on, 73 



Somerville, W., 3, 104 



Spanish phosphorite, 1 



Stead, J., 40 



Stellaria media, 24 



Temperature, effect of phosphates on 



soil, 68 



Tree Field, 49 

 Tunisian phosphates, 15, 21, 27 



effect of, on herbage, 35, 58, 59; of fine 



grinding on availability, of, 32 

 field experiments with, 31, 40 

 Tysea Hill Farm 



"accumulation of nitrogen in soil at, 76 

 effect of lime on yield of hay at, 96; 

 of phosphates on herbage at, 49 et 

 seq.; on soil texture at, 72 et seq.; 

 of rainfall on yield of hay at, 89 

 failure of clover at, 104 

 field experiments with various phos- 

 phates at, 23 

 limiting manurial factors at, 89 et seq. 



Verney, Sir H., Bart., 14 



Waggaman, 12 

 Wendens 



accumulation of nitrogen in soil at, 76 

 effect of phosphates on herbage at, 57, 

 58; of rainfall on yield of hay at, 89 

 field experiments with various phos- 

 phates at, 43 



FEINTED IN ENGLAND BY J. B. PEACE, M.A. 

 AT THE CAMBRIDGE UNIVERSITY PRESS 



