CONDUITS, PORTAGE, ETC. 
283 
loop, h, through which is passed a stirrer-bar, m n, made to sweep back 
and forth in the lower Bide of the barrel, thus to agitate and mix the 
substances considerably daring the operation of the pump, every stroke 
of the handle can sing one or two strokes of the stirrer. 
The method of inserting and extricating the stirrer-bar is as follows: 
It is raised with the pump until the end, m, comes opposite the bung- 
liole. x, through which the bar may be pulled out by the cord, tc, which 
is attached to the end, n, and also preferably to the bungs, r and 2, as 
shown. Through the same hole the bar may be inserted. This stirring 
device is i lie amplest in construct ion and operation of any yet contrived, 
while working as it does with reference to the concavity of the barrel 
it is perfectly effective. 
Pumps having other external or internal constructions than those 
■hown lieir maybe similarly mounted, and it matters little if the eye or 
the trunnion In- cither on the pump or on the Blot- piece. But some of 
the points in l he internal construction ot the pump may be briefly noticed 
here. The lower extremity of the piston-tube is closed and has a cir- 
cular scat, above which is a slot shaped entrance to the cavity of the 
piston-tnbe. Higher is another circular Seat, and immediately above it 
another inlet to the piston-tube. Between the Lwa seats is a circular 
glide- valve, which bears a packing on LtS lace and plays loose or free 
up and down as caused by the pressure to open the lower inlet during 
the downward stroke and to close it on the upward stroke. Tin* upper 
Cap of the cylinder is quite loose about the piston pipe, and holds one 
end of a sheath or tubular packing, the lower free end of which fits 
snugly around the piston pipe and tighter to the same when the fluid- 
pressnre is on the outside of it. The. piston-tube has about half the 
capacity of the outer cylinder, and the. whole arrangement is such that 
the pump discharges during both strokes, being a constant-acting or 
double acting force-pump, which operates the same whether the dis- 
charge be taken from a spout upon the side of the cylinder or from 
the side or end of the piston-tube. With the discharge from the piston 
end, and a suction ho-e upon its opposite extremity, the pump may be 
used apajrt from the barrel, like the so called " fountain pumps n and 
" hydronet tes " of the trade. Its valves are all metallic, and it may be 
made for the highest pressures or to throw any volume desired. 
This agitator-pump combination was devised for use wit h suitable ap- 
paratuses of all kinds, but in the form here presented it is especially 
designed for wheeled reservoirs, li works combined with a single de- 
li very-tube or extension pipe with or without branches or nozzles of any 
sort preferred. This device embodies the simplest suitable stirrer and 
double-acting pump for insecticide machines, is perfectly effective, and 
1 have found it the most satisfactory of all tested for squirting. 
Conduits, Frames, Portage, and Combinations of Appurtenances, without 
regard for distinctive pump characteristics, will receive more special 
consideration in the descriptions of the following devices, which are 
