206 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 



DEFLECTOR NOZZLES. 

 (Plates XIX to xxiii.) 



Under this title may be uoticed nozzles such as spread a solid jet by 

 a projecting- inclined surface against which it is forced. The deflector 

 is generallj^ used for jets of liquid, but it is also applicable for spreading, 

 directing, and dividing blasts laden with dry insect powder. The em- 

 ployment of a beveled or inclined lip as an auxiliary in slot sprays has 

 already been noticed, but in the group of nozzles which is to be con- 

 sidered now the spray is produced by the deflector alone. 



I have found that good cheap deflector nozzles are easily made by 

 cutting the plates out of thin sheet brass, copper, zinc, or tin by means 

 of a pair of stout common scissors, or by tinner's shears, by then bend- 

 ing in the curves as described below, or as indicated in Plate XX, while 

 the deflector is adjustably or separably attached very easily and satisfac- 

 torily by inserting its stem between a solid jet nozzle and a segment of 

 elastic hose or an elastic band tightly surrounding the same. 



Over the man 3^ punctured and slotted nozzles described above, these 

 have the advantage of possessing only a single round orifice, usually 

 of such size as to be less liable to choking. At least so much is true 

 of large jets for spraying broadcast over a number of rows j but jets of 

 this class from force-pump pressure and small enough for single rows 

 or for poisoning from beneath are peculiarly adapted for clogging by 

 the diminutive size necessary to give only the very limited quantity of 

 liquid needed. On this account it may be impossible to adapt this de- 

 vice quite satisfactorily to the process of poisoning from beneath. 



On the other hand, for surface sprinkling, it works very much better, 

 though lacking the highest degree of fineness. But in all cases the lip 

 resists the fluid after it is freed from pressure, thereby retarding it 

 slight!}^ and causing a little to waste by dripping or falling in large 

 drops unless forced with uncommonly great velocity. To avoid this 

 the plate should be polished exceedingly smooth and bright and not 

 allowed to rust. Also the jet must be thrown against it with great 

 force, otherwise mere adhesion of the thin, outspread film of water to 

 its surface, especially if the stream be small, causes some waste by 

 dripping. Since there is no adhesion of water to fatty substances, I 

 have tried greasing the plate, which helps to avoid friction and adhe- 

 sion of water as between metal surfaces. Certainly there seems to be 

 less drip when it is applied, while it may help to prevent rust from form- 

 ing. Also an additional pipe terminating in a funnel beneath the plate 

 to catch and return the waste to the reservoir can be used with these 

 broadcast sprinklers. 



The lip-nozzle as commonly made with a single jet has a flat deflect- 

 ing plate with a curved outline or a straight distal edge in the same 

 plane or sliglitly turned up. The spray from these naturally forms 

 denser and heavier in its center, becoming thinner towards the margins. 



