Nicotine Dust for Truck-Crop Insects. mi 
proximately the same weight of dust. The machine is carried 
strapped on the back of the operator. The cost is from $17 to $20 
each. 
The other type of hand machine, the blower gun (lig. 6; Fig. 14, 
at left), in which the air pressure is supplied by a rapidly revolving 
fan, is operated by a hand crank and gears. The flow of dust is con- 
tinuous, and the amount can be regulated by an adjustable feeding 
device. This type of machine is particularly adapted to row crops, 
as the continuous flow permits the operator to keep up a steady walk 
alongside the row, directing the cloud of dust so as to cover it com- 
Fic. 3.—Hand-operated bellows type of duster used in applying nicotine dust to melons 
for the melon aphis. 
pletely. Since no time is lost between puffs, the blower gun will 
cover a somewhat larger acreage than the bellows type, but will use 
a little more material per acre. 
Both types of hand dusters, and especially the blower gun, are 
rather laborious to operate. It has been demonstrated on small plots 
that almost 1 acre per hour can be covered with this type of duster, 
but such a pace can not be maintained for any length of time. Partly 
because of the toilsomeness of the operation, and more particularly 
because of the desirability of making the application when the air is 
still, the practice has arisen of applying the dust only for a few hours 
in the morning or evening. The average ground covered daily would 
not be over 4 acres. Hand-blower guns weigh about 10 or 12 pounds 
