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Better apparatus is required for the wet applications where success- 
ful results require the breaking up of the liquid into a fine mist-like 
spray. The essential features of such an apparatus are a force pump, 
several yards of one-half inch cloth-reinforced hose with bamboo hoist- 
ing rod, and a spray tip. The size of the apparatus will depend on the 
amount of vegetation to be treated. For limited garden work and for 
the treatment of low plants the knapsack pumps or the small bucket 
force pumps are suitable, the former costing about $14 and the latter 
from $6 to $9. 
Ready fitted pumps, knapsack and others, for the application of insee- 
ticides, are now made by all the leading pump manufacturers of this 
country, and also large reservoirs with pump attached for extended 
orchard operations, the price of the latter ranging from $25 to $75. 
The cost of a spraying outfit for orchard work may be greatly 
reduced by combining a suitable pump and fixtures with a home-con- 
structed tank or barrel, to be mounted on a cart or wagon. A spray 
tank having a capacity of about 150 gallons is a very satisfactory size, 
and may be conveniently made 4 feet long by 24 wide by 2 deep, inside 
measurements. It should be carefully constructed, so as to be water- 
tight, and should be strengthened by four iron bolts or rods across the 
ends, one each at the top and bottom. A good double-acting force 
pump may be obtained from any of the leading pump manufacturers 
at a cost of from $10 to $20, depending upon whether of iron or brass, 
and the nature of its fittings. or use in very large orchards or in city 
parks it may be advisable to construct the tank of twice the capacity 
mentioned, to expedite the spraying and to avoid the more frequent 
refillings necessary with the smaller tank. 
For the requirements last mentioned the use of power spraying 
apparatus of considerable capacity has become somewhat general, par- 
ticularly in municipal work against shade tree insects in the Hast, and 
in spraying the large citrus groves of the Pacific Slope. An appa- 
ratus of this sort recently built by the Division of Entomology of the 
Department is illustrated in the accompanying figure (fig. 3). The 
use of power apparatus for spraying is a special subject, and those 
interested would do well to consult the article by Dr. L. O. Howard 
(Yearbook Dept. Agric., 1896, pp. 69-88) giving full descriptive details, 
with figures, of the important machines now in use. 
The more economical spray tips in the amount of liquid required are 
the different styles of cyclone nozzles, the best form of which is known 
to the market generally as the Vermorel nozzle. These are manufac- 
tured by the leading spray pump companies. Other good nozzles are 
also on the market. The common garden spraying and hose nozzles 
are much too coarse for satisfactory work, and are wasteful of the 
liquid. 
A prime essential in spraying, especially where the large reservoirs 
are employed, is to keep the liquid constantly agitated to prevent the 
