2 
the casual observer to be the most unfortunate of all our Eastern cities 
from this standpoint), it is within bounds to estimate that the expendi- 
ture of $3,000 to $4,000 a year would result in green shade trees the 
summer through. This amount, moreover, will in all probability not 
need to be an annual appropriation. The first cost of a proper spray- 
ing apparatus will have to be added, but the apparatus once purchased 
and thorough work performed for two or three years, consecutively, the 
probabilities are strong that the number of shade-tree insects will be 
reduced to such an extent that a much smaller annual expenditure will 
be sufficient. 
KIND OF APPARATUS TO USE. 
The question of a proper spraying apparatus is a rather serious one, 
since in this direction a considerable amount of money should be 
expended. A steam apparatus will do the work with much greater 
rapidity than a hand pump, and yet with a strong double-acting force 
pump, which can be operated by a single man, and a tank of 100 
gallons capacity mounted on a strong cart, many large trees can be well 
sprayed in the course of a day.. From such a pump two lines of hose 
may be run with advantage. The working force of such an apparatus 
should be, a horse to draw the cart, a man to drive and do the pumping, 
and one man to each of the lines of hose. Several such machines have 
been used with good results in the work of the Gypsy Moth Com- 
mission, both for street trees and in the public parks. A steam 
apparatus, however, of such a capacity that a pressure of 75 pounds 
per square inch may be gained, will enable the operation of four or five 
lines of hose simultaneously. The rapidity of work will therefore be 
doubled, and certainly by the use of two such pumps the shade trees of 
any ordinary city can be gone over with sufficient rapidity to destroy all 
insects within the required time. A boiler mounted on a truck, the 
boiler to be complete with all fixtures—smokestack, bonnet, firing tools, 
and springs to the truck—and a pump having a capacity of 10 to 20 
gallons a minute, connected up to the boiler ready for operation, can be 
purchased for a sum well within $500. This truck should be mounted 
on wheels with broad tires. Connecting this apparatus with a proper 
tank cart would be an additional expense not to exceed $100 for a tank 
of a capacity of 200 gallons. Such an apparatus furnished with hose 
and smooth-bore nozzles of about one-sixteenth inch in diameter, when 
discharging, under 40 pounds pressure, from each of several such 
nozzles, would spray about half a gallon of insecticide mixture per nozzle 
per minute. : 
A strong steam pump to be used in connection with a small oil- 
burning boiler, the whole apparatus on a smaller scale than that 
described above, has been estimated at $275 by a prominent New York 
firm, delivered on board the cars. 
There is no reason why an old steam fire engine could not be readily 
arranged for this shade-tree spraying work. In one or two instances a 
steam fire engine has been used for this purpose without modification, 
the object being simply to knock the insects from the trees by means of 
a strong stream of water. By such means as this Col. John M. Wilson, 
U. 8. A., now Superintendent of Public Buildings and Grounds in 
Washington, kept the elms green at West Point several years ago, when 
he was superintendent of the Military Academy. In every large city 
where the fire department is necessarily kept in the best condition, an 
