533 
Iron is unfit material for spraying pumps, sulphate of copper 
destroying the nice adjustment of the working parts. So far, brass 
has given most satisfaction, and all working parts and all valves in 
contact with the spraying material should be of that or other non- 
corrosive material. Soft brass, composed of copper and zinc, 
should be avoided, as it is corroded by ammonia. Leather valves 
soon become hard and unyielding. All parts should be strong and 
easily reached for repairs, replacement, or cleaning. 
As nearly as possible, all power expended should be applied 
in forcing the material, in hand work especially. Some pumps, 
intended to be mounted on a barrel, are so constructed as to make 
the whole apparatus top-heavy and liable to accidents. It often 
happens that too much suction is also required to bring the liquid 
into the cylinder, whereas nearly all the work of the piston ought 
to be expended in forcing it. The cylinder is best at the bottom of 
Nixon’s Climax Pump on Barrel and on Tripod. 
the barrel, immersed in the liquid, where there is little or no suction 
until the barrel is nearly empty, the liquid itself doing the office of 
packing, instead of rubber, candle-wicking, leather, etc. 
The automatic stirring apparatus should be so perfect that the 
last spray that leaves the nozzle is as strong and no stronger than 
the first. Paddles worked by means of the handles, causmg up 
and down currents, involves less loss of power than when a portion 
of the liquid returns from the pump to the barrel. 
Keep trash, leaves, and sticks out of the barrel by means of a 
ud, The supply pipe leading from the pump should be provided 
vith a quick-acting valve, so as not to cause loss of spray when 
