108 HYDBOCYANIC-ACID GAS FUMIGATION IN CALIFOKNIA. 
Page. 
Cyanid of sodium, analyses of samples used for production of hydrocyanic -acid 
gas 92-93 
comparison with potassium cyanid for general fumigation. . 90 
dosages in fumigation compared with dosages of potassium 
cyanid 88-89 
first published suggestion as to use in fumigation 83-84 
inauguration of experiments by Bureau of Entomology and 
Bureau of Chemistry 84 
in fumigation of citrus trees, field tests 86-87 
kind to purchase for fumigation 88 
proportion for best yield of hydrocyanic -acid gas 93-96 
of chemicals when used for fumigation 85 
used in fumigation 85 
strength expressed in terms of potassium cyanid 85 
value for fumigation purposes 83-90 
Cyanids, action of mineral acids thereon 96-99 
effect of presence of sodium chlorid on yield of hydrocyanic -acid gas 
in fumigation 99-102 
nitrate on yield of hydrocyanic-acid gas. . 103 
Derricks for fumigating tents 20-21 
Distillate emulsion and Bordeaux mixture, injury through fumigation to trees 
sprayed therewith 72-73 
spray against citrus scales, efficiency as compared with fumigation 2 
Dosage calculation in fumigation of citrus trees 27-28 
factors affecting it in fumigation 52-53 
formula for measuring fumigating tents 28 
schedule A, for high grade sodium cyanid 88 
No. 1 , for potassium cyanid 34 
|, for potassium cyanid 59 
|-A, for high grade sodium cyanid 88 
under improved system (with potassium cyanid) 34-37 
Dosages for scale pests in general (with potassium cyanid) 61 
" Firing' ' effect produced in orchards by purple scale 8 
Fumigation against black scale 59-60 
mealy-bug 63-64 
purple scale 53-57 
difficulty of destroying scale on fruit 56-57 
dosage for eradication (with potassium cyanid). 55-56 
length of exposure 55 
two successive treatments 57 
red scale 57-58 
dosage with potassium cyanid 58 
yellow scale 60-61 
chemistry thereof 91-105 
summary 104-105 
generators, device for covering them 74-76 
of citrus trees 1-81 
apparatus 10-24 
appearance of fumigated trees 73 
by associations : 5 
contract 4-5 
counties 5 
private individuals 5-6 
