41 
which works in the cylinder consists of a cone-shaped brass casting 
into which is fastened a similarly shaped piece of soft rubber, the base 
of the latter being a little larger than that of the former. 
These various parts are all plainly shown at Fig. 8, a being the 
piston rod, b the cone-shaped brass receptacle for holding the piece of 
soft rubber shown at c. In Fig. 10 are shown the parts used in fastening 
the rubber to the brass cone, a being the end of the piston rod with 
screw thread, b tap, and c casting which fits between the tap and cone 
and holds the rubber in place. This casting is shown enlarged at Fig. 
9. The manner of working the pump will be better understood by con¬ 
sulting Fig. 11 in which the flow of the liquid is represented by the 
arrows. When the piston is raised the liquid is drawn in at the open¬ 
ing a. The downstroke forces the liquid through the pipe b into the 
air chamber c and at the same time closes the ball valve d. Another 
upstroke is made and the ball valve e closes the opening at that point, 
thereby preventing the liquid from rushing back into the pump cylin¬ 
der. This process being repeated the liquid remains under constant 
pressure in the air chamber and as a result it is forced through the 
hose, lance and nozzle shown in Fig. 1 in a constant spray. The lance 
and nozzle we use on this machine is the well known improved Vermorel. 
The other parts of the apparatus, such as the straps, handle, lever, etc., 
need no special mention, as any machinist will be able to see from the 
drawings how they are made and used. For the further benefit of any 
one desiring to manufacture the pump the dimensions of the various parts 
are given in detail at the close of the article. 
As regards cost, the machine with two lances and nozzles sells 
in France for 40 francs, or about $8. The duty, transportation, and 
other charges on the pump will bring the cost, laid down in this coun¬ 
try, up to about $20. This is for a single machine. Where a number 
are ordered at a time they can be delivered here for about $15 each. 
Estimating labor at 40 cents an hour the machine complete, as we have 
described it, can be made in this country for about $11.50. 
If special appliances are used and the machines are turned out in 
large numbers, we see no reason why the actual cost of manufacturing 
could not be further reduced to $10.50 or even to $10 each. Manufac¬ 
turing them at this price, it seems to us that they could be put on the 
market for $12 or $14 at a fair profit. 
DIMENSIONS OF PARTS DESCRIBED ABOVE. 
Reservoir, 17x13^x4£ inches. 
Opening for liquid, 4£x7f inches. 
Opening for piston rod, f of an inch in diameter. 
Opening for introduction of air chamber (a and 6, Fig. 3), f inch in diameter. 
Strainer, fx4£x£ inches. 
Air chamber, 2^x12^ inches. 
Pump cylinder, 2^x4f inches. 
Diameter of piston rod at top, £ inch. 
Length of piston rod, 13£ inches. 
Diameter .of cone-shaped casting (Fig. 9), 2£ inches. 
Height of cone-shaped casting, 2 inches. 
