xii CONTENTS 



SECTION IV. MANURES FOR SPECIAL 



CROPS. 



Cereals . . . . . . . . . . . 216 



Root crops . . . . . . . . . . . .217 



Grass lands ........... 221 



Pasture ............ 222 



References 223 



PART V. THE FUTURE OF FERTILIZERS. 



SECTION L NEW SOURCES OF 

 FERTILIZERS. 



New sources of nitrogen . . . . . . . . .224 



References ............ 228 



SECTION II. IMPROVEMENTS IN THE 

 MANUFACTURE OF FERTILIZERS. 



Compound manures : the Cotrell process ...... 229 



References . 232 



SECTION III. IMPROVEMENTS IN THE 

 USE OF FERTILIZERS. 



Labour and fertilizers .......... 233 



References 238 



PART VI. CHEMICAL INSECTICIDES AND 

 FUNGICIDES. 



SECTION L INORGANIC POISONS. 



Metallic salts of mercury, copper, lead, arsenic ..... 239 

 Non-metals, boron compounds, sulphides and polysulphides . . . 245 

 References ........... 248 



SECTION II. ORGANIC POISONS. 



Carbon di-sulphide, formalin, prussic acid, petroleum, soap . . 249 



Coal tar derivatives . . .251 



Vegetable extracts 253 



References 254 



GENERAL BIBLIOGRAPHY 257 



INDEX 259 



