XVI TABLE OF CONTENTS. 



PAl.E 



68. Sulphate of Iron (green vitriol), FeS047HjO. 



Manufacture 171 



Properties ..--.-.-.. . . 171 



Action on plants - . . . 171-4 



Action on fuu;,'i 174 



Comparative action of blue and green vitr'ol on spores - - . . 174-5 



Action on insects 175 



Use 175 



Use against chlorosis 175 



Use as a weedkiller 176 



Destruction of moss 177-8 



On meadows and lawns 177-8 



On trees 178 



On roofs 178 



Destruction of dodder 178 



Use against plant diseases 178-9 



Application of green vitriol to the soil 179 



Use on aerial part of plant - - - 180-1 



(n) As spray ISO 



(6) As a coating - 180-1 



Use as an injection in the trunk 181 



Use against cryptogamic diseases of plants 182 



Use against potato scab 182 



Use against potato disease 182 



Use as a pickle for seed-corn 183-4, 18-5 



Use against grape rot .-.-----. 185-6 



Use against insects - 186-7 



69. Febbic Sulphate, Fe2(S04)3. 



Preparation ------------ 187 



Properties - - - 187 



Use - - 187 



70. Ferrocyanide of Potassium, K4FeCy6. 



Preparation 187 



Use 187 



Action on plants 188 



71. Prussian Blue (ferric ferrocyanide), FeyCy^g. 



Discovery 188 



Preparation 188 



Use 188 



Trial as pickle for seed-corn 188 



Trial as spray for growing oats and summer wheat and pear-trees - - 188 



72. Bobate of Iron, FeB407. 



Preparation 188 



Properties 188 



Use - 188 



Formula for bouillie 188 



Trial of such against leaf spots of pear-tree and chestnut-tree - - 188 



CHAPTER XI. 



Potassium Bichromate (Bichrome) — Chbome Alum— Potassium Pebmanganate — 

 Manganese Sulphate — Nickel Sulphate — Cobalt Sulphate. 



( Tii. Potassium Bichromate, KjCrjO, 189 



\ 74. Chrome Alum, K2S04Cr2(S04)324H20 189 



Preparation ------------ 189 



Properties 189 



Action of chrome salts on plants 189 



Action on parasitic fungi 189 



