196 REPOET 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 



ent sizes are offered, and there is a series of face plates substitutive for 

 each otlier, but differing in the sizes and number of perforations. 



Peripheral-roses [divided]. — Mr. J. C.Melcher, of Black Jack 

 Springs, Tex., devised a discoid sprinkler head with a many-punctured 

 circumference, i)atented in 187G (I^o. 172467). This is now made with a 

 lid clamped fast by a screw and removable for cleaning out the interior. 



To Mr. George Yeager, of Flatouia, Tex , was granted in 187;) (No. 

 219337) what he regards as an improvement in nozzles of this style, 

 which consists in closing the top and base with sheet-metal screw- caps, 

 detachable for taking out accumulations from within, while the cap held 

 lowest serves to store the heavy sediments. 



A nozzle, Plate XY, Fig. 6, producing this form of spray, is used on 

 the Euhmann sprinkler, but the arrangement for cleaning the interior is 

 different, as may be seen in a sectional view, Plate XY, Fig. 7. By 

 turning the T-shaped thumb-handle above, a small brush inside is made 

 to sweep the inner surface of the punctured rim. It will be seen that 

 s'uch sweeping may be kept up constantly by an automatic iirocess 

 to be described in chapter XIII. For others see p. 193 and Pi. XIY, 

 Figs. 1 and 2. 



EosE-co^tBiNATiONS. — There are many attempts to combine the rose- 

 head and solid-jet pipe in one nozzle. This is done satisfactorily by- 

 having the rose separable from the pipe by a clutch, or screw coupling, 

 a plan which has been already spoken of, but which is illustrated in 

 longitudinal section in Plate XY, Fig. 1 representing a nozzle patented 

 in 1874 (Xo. 150742) by Messrs. W. Barry and L. H. Prentice, of Cbi- 

 cago, 111. The circle shows the plug- cock perforated by the cavity of 

 the solid-jet pipe that terminates inside of the rose-head &, which can 

 be separated and screwed upon the nib <?, for carrying it while a solid jet 

 is used. Compare the clutch-rose, p. 195. 



Several other devices for combining the rose and solid-jet in one noz- 

 zle have been found, but they are usually either a little too complex or 

 costly to become popular, or else the construction is such as to impair 

 either the spray or the solid-jet, or both. 



SLOT-NOZZLES. 

 [Plates XVI, XVII, and XVIII.] 



In slot-nozzles the form of the spray is given by a slot or group of 

 slots from which it is emitted. The fluid forced from a slot expands 

 in a somewhat fan-like shape, and then breaks up into a sheet of spray. 



The best of these are such as have a slightly divergent discharge 

 from the side of an eddy-chamber, with or without a deflector lip. - The 

 examples shown on Plate XYI, Figs. 4 and 5, now seem to be the 

 most valuable, though, for broadcast work, such kinds as are shown in 

 Figs. 1, 2, and 3 may sometimes be selected. 



To lessen the clogging of small jets adapted to poisoning from be- 

 neath, only a single slot can be safely used, its lips should be far apart^ 



