CONTENTS 



CHAPTER PAGE 



I. THE NITRATE PROBLEM I 



ii. ENGLAND'S FOOD-SUPPLY IN PEACE AND WAR - n 



III. BACTERIA AND PROTOZOA - - IQ 



IV. PEAT AND ITS USES - - - "31 

 V. FIXATION OF NITROGEN BY LEGUMINOUS PLANTS 46 



VI. HUMUS ... 64 

 VII. BACTERIZED PEAT I ITS PREPARATION AND 



GENERAL PROPERTIES - - 8 1 

 VIII. VITAMINES, ACCESSORY FOOD BODIES, AND AUXI- 



MONES - - - - 96 

 IX. ELEMENTARY CONCEPTIONS OF CHEMISTRY IN 



RELATION TO THE SOIL - - - IIQ 



X. THE TESTING OF HUMOGEN - - - 135 



XI. THE PREPARATION OF HUMOGEN - - 150 



XII. PRESS AND OTHER CRITICISM ... 155 



XIII. HOW HUMOGEN IS APPLIED - - 169 



XIV. GENERAL RESULTS - 1 78 

 XV. HINTS AND EXPERIMENTS ... 197 



APPENDICES ..... 205 



LIST OF PAPERS - .... 239 



INDEX ...... 241 



