152 



THE GYPSY MOTH. 



The stream from the hose is carried through the bent tube 

 and enters at a tangent the anterior chamber of the cylinder. 

 The posterior chamber serves as a packing box for a small 

 brass rod which passes through the centre of the partition 

 dividing the chambers, and lying in the axis of the cylinder, 

 projects half its length in the rear, where it is terminated by 

 a screw cap. Around the rod between this cap and the nut 

 closing the packing box is a spiral spring which keeps the 

 rod drawn back when not in use. The anterior part of the 

 rod has a flange in front of the partition which prevents it 

 from being drawn back out of the chamber and its anterior 

 end has a fine needle point. The outer chamber of the noz- 

 zle is closed by a screw cap, hollowed at its centre where it 

 is perforated by a fine hole which serves as the exit for the 

 spray. When this hole becomes clogged, it may be cleared 

 by pressing on the cap or thumbpiece at the base of the rod, 

 thus forcing the needle poin*t out through the opening. 



The climax or Nixon nozzle is better adapted for spraying 

 large orchard trees than the cyclone, as it throws a good 

 spray to a considerable distance, but it is not adjustable like 

 the Gem and Lowell nozzles. It is shown in Plate XXIY., 

 Fig. 3. No. 1 shows the entire nozzle. No. 2 the nipple 

 end of the same, and No. 3 the end of the nozzle, which 

 screws over the nipple and is covered with a fine screen 

 which breaks up the stream into spray. All these parts are 

 fitted with standard pipe thread, and will fit corresponding 

 sizes of gas pipe and hose coupling. They are made of 

 various sizes which will produce spray from the density of 

 a heavy fog to any coarseness that may be required, the 

 smaller sizes giving the finest spray. 



The McGowen nozzle (Plate XXYH., Figs. 3, 4 and 5) 

 has been used only experimentally in the gypsy-moth work. 

 This is the only nozzle we have yet used which appears to 

 give equal satisfaction in all kinds of spraying. It pos- 

 sesses to some extent the qualities of all the nozzles previ- 

 ously mentioned. It can be regulated at will to throw a fine 

 spray, project a coarse spray to some distance, or send a 

 stream to a considerable height, where it will break into 

 fine drops. Its efiective use, however, requires some skill 

 and mechanical knowledge on the part of the workman. 



