4 MISC. PUBLICATION 35, U. 8. DEPT. OF AGRICULTURE 
dust guns cost from $12 to $20 each, and one gun can not be used 
to dust more than 8 acres of cotton in any one season. It is very 
hard work to operate one of these little machines all day long. | 
The 1-mule machine (fig. 7) is pulled by a mule or horse that walks 
between two rows of cotton. There are two nozzles sticking out 
behind this machine, as you can see in the picture, and the poison 
dust is blown through them onto two or three rows of cotton as the 
machine moves through the field. This machine costs from $75 to 
$125, and one machine can be used to dust as much as 60 acres of 
cotton each season. It will dust 15 to 20 acres in a single night. 
The cart machine (fig. 8) has two wheels that straddle a row of 
cotton and is drawn by two mules or horses. It has three nozzles 
and will poison from 25 to 30 acres of cotton in a single night. One 
I'ic. 7.—The 1-mule dusting machine is pulled by a mule or horse that walks be- 
tween two rows of cotton. The poison dust is blown through two nozzles onto two 
or three rows of cotton as the machine moves through the field 
such machine can not be used to poison more than 100 acres of cotton 
through the season. 
Within the last few years the airplane, too, has come to be used 
as a dusting machine. (Fig. 9.) Of course this does not mean 
that any airplane can be used for this work. The low flying that is 
done while dusting cotton is more dangerous than that done hich up 
in the air. The plane has to be flown close to the ground, sometimes 
almost touching the cotton plants, and it can not be flown as fast as 
those high up in the air. Fortunately for those doing this kind of 
work there are specially built planes which can stay in the air while 
going much slower than can ordinary planes. 
