214 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 



struction and what now seems the best combinations of the parts of isome 

 of the nozzles of this group. 



First we may notice a number of eddy -jets, as involving the principles 

 which seem the best for poisoning the fields, and which are the only nozzles 

 suited for applying poison properly to the under surfaces of the foliage. 

 In all these the rotation chambers and the inlets and outlets of the same 

 are essentially of the kinds already described, but we need to examine 

 a few styles selected and illustrated to show particularly some of the 

 details of construction, form, and size. 



Fig. 1, Plate XXIV, presents a plan view of one of the larger typical 

 eddy -jets as cheaply made of thin sheet-metal. The spout, a, is shown 

 in section to its inlet-discharge, x. The arrows indicate the course of 

 the fluid through the chamber, c, and from its central outlet-discharge, s. 

 The whorl of tangents is intended to show the plan of dispersion of the 

 spray which flies off from the margins of the outlet, s, A plan section of 

 the chamber, c, is shown also in Fig. 1, where x marks the eccentric inlet 

 and one arrow shows the current of water entering from the spout, a, 

 while another gives an idea of the angle of tangential discharge from 

 the outlet, 8. If desired, the side of the chamber might be furnished with 

 an opening, closed by a lid, cap, or plug. The orifices are so large that 

 clogging and cleaning out will hardly be necessary in nozzles of this 

 size; but when these are reduced for small sprays suited to spraying the 

 under surfaces of small plants, a means of opening the chamber to clean 

 it out had better be provided. A nozzle of this pattern is very cheap, 

 and in the size indicated will throw a remarkably large, fine spray for 

 broadcast work, varying according to the force applied ; but with a com- 

 mon syringe pump or hydronette the single jet is easily spread 30 feet 

 wide and distant. Xozzles of this general style seem to be the best for 

 spraying either above or beneath. 



To get extremely large and broad sprays the orifices may be increased. 

 As in Plate XXIY, Fig. 2, the capacity of the inlet, x^ may equal the 

 caliber of its spout, a, and the jet-hole, §, may be much larger, leaving 

 only a very narrow margin, c, to represent the excurrent face. With 

 such an outlet the angle of dispersion is very much wider and the widest 

 sprays for broadcast throwing can be made. 



But for all ordinary purposes there is no need of making the nozzle 

 of such large size. Indeed, the very small size shown in Plate XXV, Fig. 

 4, gives a very large spray well suited for broadcast work. A plan sec- 

 tion of the same is shown also. In both figures a marks the spout, x 

 its eccentric, tangential inlet to the chamber, c e, and s the outlet. The 

 chamber is formed in a removable plug, e, inserted into the cap, Avhich is 

 fixed to the spout, a. The tangential inlet perforates both the plug and 

 the cap, while the central outlet perforates the cap only. 



A nozzle of the same style, but with a smaller outlet, is represented 

 in Plate XXV, Fig. 2. This and those in Figs. 1, 3, and 6 will exhibit 

 what are suitable standard sizes for small jets to throw poison upward 



