40 



CIRCULAR 3 6 9, U. S. DEPARTMENT OF AGRICULTURE 



discussed in other publications of the Department. 6 No attempt is 

 made to discuss the fumigation of any commodity from a quarantine 

 standpoint. For more detailed information regarding the treatment 

 of any commodity discussed in the following pages, or regarding 

 commodities not mentioned, the reader should direct inquiries to 

 the Bureau of Entomology and . Plant Quarantine, United States 

 Department of Agriculture. Washington, D. C. 



Figure 31. — Automatic record of four vacuum fumigations conducted during a 

 period of 24 hours. Hours of day and night are indicated on the circum- 

 ference of the chart. Figures in circles indicate: (1) Vacuum pump started; 

 (2) chamber exhausted to 28.5 inches of mercury; (3) fumigant (ethylene 

 oxide-carbon dioxide mixture) introduced; (4) treatment period of 2 hours; 

 (5) vacuum pump operating and breaker valve opened simultaneously, pro- 

 viding an air wash of product fumigated; (6) treatment cycles similar to 

 (4) ; (7) last fumigation of day allowed to continue overnight; (8) doors 

 opened, commodity removed, and a new lot placed in chamber; (9) vacuum 

 pump started before breaker valves were opened, accounting for the rise 

 in vacuum at this point. 



Confectionery 



Since the insect problems of the candy and nut-meat industries are 

 rather closely associated, it seems logical to discuss them under one 

 heading. Nut meats are highly susceptible to insect attack, and 



6 U. S. Department of Agriculture Farmers' Bulletin 1260, Stored-Grain Pests ; Farmers' 

 Bulletin 1275. Weevils in Beans and Peas ; Farmers' Bulletin 1811, Control of Insects 

 Attacking Grain in Farm Storage ; and Farmers' Bulletin 1880, Control of Insect Pests of 

 Grain in Elevator Storage. 



