REMEDIES AGAINST FOREST INSECTS. 45 
motion of the liquid, which issues in a funnel-shaped spray through a 
central outlet in the adjustable cap. The breadth or height, fineness or 
coarseness of the spray depend on certain details in the proportion of 
the parts, particularly of the central outlet." 
Fig. 11 shows two styles of this nozzle, which I have adopted from a 
host of experimental forms as the best for all ordinary work. At A is 
shown the typical small-stemmed nozzle, with the screw cap removed 
to show the inlet orifice d. At B is shown a sectional view of the same 
again with the cap removed, showing the tangential entrance to the 
chamber a through the orifice e, which when the cap is inserted coincides 
with the orifice d. At is shown a face view of the cap c, which should 
be countersunk about the orifice of exit on the exterior surface only ; 
and also an outline drawing of a chamber placed at an angle of 45° 
with the stem — a form of advantage especially in overhead spraying. 
The stem may be inserted into the discharge-pipe and fastened by 
wrapping tightly with copper wire, or a more convenient form is made 
with a female screw of a size to fit a three-eighth inch nipple. The 
nipple is inserted into the discharge-pipe and fastened in the ordinary 
manner, and allows an easy interchange of nozzles of different sizes or 
patterns. A discharge orifice of about one-sixty-fourth of an inch may 
be used for a very fine spray ; for coarser and heavier work a one-six- 
teenth-inch orifice will be preferable. 
The value of rotating the liquid to break it up into a suitable spray 
and to prevent clogging, which are the essential features of the Riley 
nozzle, has been universally recognized. 
In this country, owing to the fact that this nozzle has not been pat- 
ented and is not pushed by interested parties as are patented contriv- 
ances, it has not come into such general use as its merits warrant or 
as has accompanied the introduction of patented modifications of it in 
other countries. It is now, however, being quite extensively manufact- 
ured and offered by the trade, and a number of modifications of this 
nozzle have appeared in France, which, while adding certain new feat- 
ures, have not departed from the valuable principle of the typical form, 
viz : that of the centrifugal motion of the liquid. These nozzles are 
employed in France, Germany, and other European countries almost 
to the exclusion of all other forms, and in this country they are also 
extensively used. More recently a valuable modification has appeared 
in this country, the Universal Spray Tip, and in New Zealand a com- 
pound form is manufactured, known as the New Zealand Triplet, and 
fashioned after one which I used and described in California in 1887. 
A full description of the important modifications of the Riley nozzle 
that have appeared in this and in foreign countries is given by me in 
Insect Life, Vol. I, Nos. 8 and 9, to which the reader is referred for fuller 
details. 
In this country, these nozzles are manufactured under contract, for 
dealers, by Thomas Somerville & Son, Washington, D. C, and by 
