CENTRIFUGAL NOZZLES. 217 



form may be used to eject the spray higher. Also, the funnel-shaped 

 cavity directs any choking materials to the outlet, rendering it more 

 likely to clog than is the orifice through a flat face. The to[) or base 

 may be opened by a lid, plug, or cap for removing foreign objects that 

 obstruct. The construction and i)lan section shown at Plate XXV, 

 Fig. 6, is very satisfactory. The spout, «, has the usual eccentric en- 

 trance, ic, into the conical chamber, c, having an outlet, s, and being 

 formed in the plug, e, removable from the cap, c, which is fast to the pipe, 

 a. Where the chamber is conical, the more its altitude exceeds the 

 diameter of its base the more coarsely, farther, and narrowly will the 

 spray be thrown, and, inversely, the more the basal width surpasses 

 the height the broader and finer and less distant will tlie spray discharge, 

 as shown by my experiments with a series of these forms. Eounded 

 convexity or concavity of the discharge-face does not give to the spray 

 any very marked difl:'erence from that derived from a plane face, because 

 the parr, immediately bordering on the outlet in such forms is almost 

 flat. Another form of nozzle, having a shallow funnel-shaped face pro- 

 jecting into the rotation cavity, seems less easily clogged than either of 

 the others. 



For some apparatuses it is desirable to have nozzles discharging at odd 

 angles, or with direct discharge, and often with solid jet combinations; 

 hence, some of those which have been made for such purposes will be 

 described. 



When it is desired to use a single large spray projected straight away 

 from the person holding the nozzle, the device given in Plate XXYI, Fig. 

 1, is satisfactory. It is an eddy-chamber with a handle, and represented 

 in section. The incurrent spout, a, connects with a hose, and opens by 

 the usual tangential hole, x, into the chamber, c, which is comi^osed of 

 the hollow plug, e, and the separate discharge-face,/, held upon the open 

 end of the plug bj" the cap, c', from which the crown is cut out so as to 

 leave only a narrow border to bind down the face-plate. This plate is 

 removable, and others, with outlets of different sizes, are substitutive 

 for it, to get sprays of all sizes desired. The outlet here shows lips of 

 a form deserving special attention. It is seen to have a bugle-shaped 

 increasing expansion, by which a broader spray can be made than by a 

 straight cut hole, as explained above. The base or plug has its center 

 perforated by a large screw on the handle, v, and which can have its end 

 screwed toward or against the outlet to limit the volume thrown, or en- 

 tirely close the outlet, and thus serve as a shut-off plug. 



In the examples so far given we have observed the inlet spout inser- 

 ted parallel to the plane of the face or base of the nozzle, but it is some- 

 times advantageous to insert it at an angle with this plane and either 

 on the face or base or periphery. Plate XXIV, Fig. 4, shows one with 

 the spout inclined diagonally upward from the outer part of the face. 

 This spout prolonged makes a very convenient long handle for holding 

 a single nozzle so as to discharge vertically beneath plants. 



