244 



the wall of this chamber. These parts must meet accurately when 

 lid is screwed down or the working of the nozzle is interfered with. 

 To overcome this somewhat, a transverse slotted opening is sometimes 

 made at d. Most of the French modifications make the cap to screw 

 over the outside, but this necessarily increases the vertical depth of the 

 chamber and considerably alters the character of the spray, tending to 

 make it coarser, but at the same time to give it greater propulsive force 

 In a direct liuefrom the discharge orifice. 



Fig. 5-1— The Riley or Cyclone nozzle 



For a fine mist of spreading spray the best results are obtained with 

 a shallow chamber like the one shown. The face of the cap should be 

 of fairly heavy metal, countersunk on the exterior surface, leaving but 

 a thin plate of metal at the orifice of exit. The inner surface should 

 never be countersunk around this orifice, as is often done by manufact- 

 urers. The section at B shows the construction of the stem and cham- 

 ber and the tangential entrance orifice at the bottom of the chamber. 

 At C is shown a view of the upper surfiice of the cap c, and also an out- 

 line drawing of a chamber placed at an angle of 45 degrees with the 

 stem. This last is an important modification, especially when spray- 

 ing overhead, as by slightly inclining the supporting-rod the spray can 

 be deliv^ered upward in a nearly vertical direction. 



The size of the stem is merely a matter of convenience to suit the de- 

 sire of the user. In the work of the Division this has been made of 

 suitable size to insert in five-sixteenths or one-quarter-inch rubber tubing, 

 as we found these the most convenient sizes of discharge-pipe to use. 

 A wire wrapped tightly around the tube over the stem makes a per- 

 fectly tight joint and answers all purposes. 



Of late, however, when it has become desirable to use the different 

 sizes and styles of nozzles for the many and varied purposes to which 

 spray machinery is now put, we have used a stem carrying a female 

 screw of the size to fit a three-eighths-inch nipple. This nipple is made 

 with a stem to insert in the size of the discharge pipe which it is de- 

 signed to use, and a slight shoulder permits of more secure fastening 



