New York AGRICULTURAL EXPERIMENT STATION. 699 
atime. The wagon is kept slowly moving; the driver directs the 
spray from his two nozzles at the lower branches, while a man 
in the rear standing ona platform is able to reach the uppcr 
part of the tree. A third man is required to work the pump. 
In spraying larger trees it is, of course, necessary to stop at each 
tree, and the hose should be provided with bamboo extensions. 
An outfit like the above is easily and cheaply rigged up and 
will be found to be more satisfactory for this work than the 
expensive power machines. 
Pomps. 
For the ordinary orchardist some form of a hand force pump 
mounted on a tank or barrel drawn in a wagon serves his pur- 
pose best. The pumps for spraying copper compounds should be 
made of brass or be brass lined, otherwise they soon become cor- 
roded. They should havea double discharge, as two leads of 
hose are usually needed. Many good pumps are on the market, 
and it would be difficult to say which is best. 
For convenience of discussion, pumps that are used in spraying 
may be divided into suction, displacement, rotary and semi-rotary 
pumps. ' 
In suction pumps the piston head is commonly packed with 
commercial packing, which needs to be frequently replaced. 
As the packing begins to wear, the gritty particles of the spray 
mixture work into it, causing it to become stiff and harsh. Care 
should be taken to change it before it gets in this condition. 
If-allowed to remain, the cap must be screwed down tightly 
to prevent leaking, which causes the pump to work hard, while 
the gritty plunger cuts the cylinder and soon wears it out. If 
the valves are rubber balls they should be replaced with marbles 
when spraying kerosene emulsion, as the kerosene causes the 
rubber to swell so that the balls can not move. This style of 
pump does good work when properly taken care of. The piston 
and valves are hard to get at, and it is a question whether the 
time necessary to keep them in order will offset the higher price 
that must be paid for a pump in which this constant attention is 
not necessary. 
In displacement pumps the plunger displaces its own volume of 
liquid. In the later patterns the valves are on the outside and 
can be gotten at by simply unscrewing the cap, without taking 
