CONTENTS. 



Tage. 



Introduction 83 



Strength of sodium cyanid expressed in terms of potassium cyanid 85 



Proportion of chemicals 85 



Field tests 86 



Action of sodium chlorid 87 



The kind of cyanid to purchase 88 



Dosages with sodium cyanid 88 



Dosages recommended for scale pests 89 



Comparison of sodium cyanid and potassium cyanid for general fumigation 90 



ILLUSTRATIONS. 



PLATES. 



Page. 



Plate IX. Dosage Schedule A, for high-grade sodium cyanid 88 



X. Dosage Schedule f-A, for high-grade sodium cyanid 88 



82509°— 11 



III 



