INDEX. 313 



PAGE 



dams 152 



decay of vegetable matter 9, 61-63, 246-248 



denitriiication 64 



dew, effect of 17 



formation of 15, 16 



impurities in 10 



diffusion 69 



' ' dineba " 208 



diseases, spread by wind 18 



doddar 104. 



drainage 23, 32, 45, 52-58, 81, 150-166 



drainage water, contents of 34. 



" durah." See millet and maize. 



dust, effects on plants 11 



earthnuts 78 



energy 8, 17 



" erd asfar " 22 



iswid" 22 



" erilla " 105 



Etsa, soil from 24 



evaporation from soil 11, 41, 57, 100 



water 14, 15 



Facus, soil from 58, 79 



fallowing 89, 105 



"fass" 107 



" fassing " 49, 57, 98 



Fayoum, soil from 24 



water-wheel of 175 



felspar 25 



fermentation. See decay. 



fertility of soil 29, 30, 80, 217 



fixation of plant food 34-36, 288 



flax 83 



flocculation. See coagulation. 



fog 15 



food of plants 27, 222 



amount in soil 30 



how absorbed 68-74 



forest 11 



frost 13 



germination 12 



Ghizeh, nitrogen in rain at 10 



goosefoot 105 



grubber 96 



guano 283, 284 



