THE IMPORTED ELM LEAF-BEETLE. 21 
zle having a direct discharge by bending it to one side. The nozzle, n, 
and spray, s, are directed laterally, and the nozzle, n, is maintained in 
this position by a metallic hook or eye, 2, 
Z/ having a crooked stem inserted at the side 
as of the hose in the end of the pole. Where 
the side spray is permanently desired, the 
metallic stem is inserted inside the hose 
and connected with the base of the nozzle, 
or the tubular stem of the nozzle is given 
the desired crook. For small trees the 
simpler extension pipe shown in Fig. 5 is 
satisfactory The metallic tube, ¢, several 
feet in length, is used as the stiff part, ¢, 
connected with the hose, h. One longer 
metallic pipe, having telescopic sections 
made tight by outside segments of rubber 
tubing, has also been employed, and is a 
very desirable extension pipe. Where 
only low end-spraying is to be done, as 
upon small trees, &e., the eddy-chamber 
nozzle (Fig. &) is set upon such a pipe, or 
upon its own stem, so as to discharge at = il 
right angles therefrom ; but a diagonal po. ranean 
sition of the chamber, », on its stem, 7, Wi diagonal 
nozzle: hose, h; 
throws the spray, s, at an intermediate ™ct#llicpipe.t; 
diagonal eddv 
, 7 j as ir v sha ber = 
angle between the right angle and a direct hamper, ney 
aes ener of line, by which, without any readjustment, pales ne 
peeing ieee ee the spray, s, can be directed higher or 
wasber, j 5 ee lower. beneath the foliage or above. For general use, 
chambernozzle,nm; this kind of nozzle is the best. It consists of a shal- 
“ea a low, circular, metal-chamber (Fig. 6, ¢), soldered to a 
short piece of metal tubing, a,as an inlet. The inlet passage, xv, pene- 
trates the wall of the chamber tangentially, admitting the fluid eccen- 
trically, and causing it to rotate rapidly in the chamber. The outlet 
consists of a small hole, s, drilled in the exact center of the face, e, of 
the chamber, and through this outlet the fluid is driven perpendicu- 
larly to the plane of rotation in the chamber, and converted into a 
very fine spray. For a full description of this nozzle the reader is re- 
ferred to our report as Entomologist to the Department of Agriculture 
for the years 1881-82, p. 162. With ordinary force-pump pressure the 
discharge-hole of the nozzle is about one-sixteenth of an inch in diam- 
eter for misty sprays with particles invisibly small. Rather than use 
the larger, coarser sprays, which were usually employed in these tests, 
it is better to use the finest spray. The spray falling upon the exten- 
sion pipe soon accumulates enough to flow down the pole and wet the 
hands. To prevent this a wrapping washer of leather or other flange 
