222 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 
Yet these in turn are surpassed by the blowers treated in the following 
chapter. 
Rotated orifices. — If a tube supplied with water, even without 
water pressure, be whirled, the centrifugal force will cause the water to 
flow through it and fly off from its distal end in the form of a circular 
broadcast spray. The devices I have contrived to test the possibility 
of utilizing this principle show that it can be used for coarse sprinkling 
and that sprays may thus be easily thrown 25 or 30 feet wide. 
Pronged reels. — When liquid is allowed to flow onto the axis of a 
group of radiating, whirling prongs of wire or other material, a Centrifugal 
action appears in the fluid following the prongs causing it to fly off from 
their extremities, thus producing a circular shower. As such reels and 
stiff brushes grade into each other, they may be noticed further under the 
following paragraph. 
Brush poison-throwers. — If a brush of any sort be supplied with 
fluid or dry poison, and its bristles be sprung, their elastic recoil im- 
parts a centrifugal force to the material which will be thrown in a spray. 
Also if a cylindriform brush, or one of any other shape, be rotated rap- 
idly, the centrifugal force will disperse the poison fed to it, whether the 
bristles be sprung or not. Utilizing these principles some machines 
have been constructed which promise much, and will be described here- 
after. The following kinds of fiber have been tested to get their rela- 
tive values in brushes for this purpose: 1, broom corn; 2, stout bristles ; 
3, tampico; 4, so-called sea-root; 5, spintered woods; 6, split goose 
quills; 7, whalebone; 8, coarse hemp; 9, wire. 
Any of these answer for sprinkling or powdering from above, and, 
where plants are very low, for poisoning from beneath ; but where poison 
is to be thrown from below upwards into plants as tall as cotton, the 
more stiff and longer fibers answer best. Broom-corn proves the most 
satisfactory for throwing powder on account of its length, strength, 
elasticity, and cheapness. In these brushes the straws or bristles should 
not be iuserted densely, but ought to have plenty of room to flex and 
recoil freely. A very good size for the brush is 7 inches diameter and 
4 or 5 inches in length. 
Very s*"out hog-bristles work well, but are almost too expensive. They 
tbrow a finer spray than broom-corn, but not so far. Also the moisture 
destroys their stiffness and elasticity more than that of the corn. 
Tampico brushes throw powder and liquid nicely, but the fiber is not 
durable enough. It loses strength and breaks off or wears out too soon. 
The so-called sea-root brushes work only tolerably well. The mate- 
rial is as strong as broom-corn and somewhat similar in appearance, but 
its fiber has not the length, stiffness, and elasticity of the latter. 
Quills from geese or other fowls will also answer. They should be 
split in halves, or thirds, or quarters, and inserted with shellacked pegs 
into a cylindrical wooden core or hub. The quills soften greatly, from 
being wet, and hence lose their stiffness and straightness very soon if 
