8 
Insecticide Apparatus.—For the making of emulsions and the appli- 
cation of insecticides a good force pump is essential. The best appa- 
ratus for the making of an emulsion is one of the small hand pumps 
known as hydronets or aquapults, which are manufactured by all 
pump makers, the Johnson type being preferable. For the applica- 
tion of sprays to trees either the knapsack pumps for small trees and 
young orchards and nursery stock, or the larger cart or barrel pumps, 
will be desirable. The aquapult or hydronet can be obtained for 
about $9 and the knapsack pumps for about $15. The larger barrel 
and tank pumps, when arranged ready for use, range in price from $25 
to $75, depending on the size and complexity of the machinery. 
A very satisfactory apparatus can be made at much less cost by buy- 
ing a good force pump at a cost of $9 to $12, and fixing it to a strong 
barrel or wooden tank. All the pump manufacturers have pumps 
that are adapted to this purpose, and the cost of the apparatus by this 
means will be limited practically to the cost of the pumps, nozzles, and 
hose, which should not exceed at the outside $15. 
The nozzle in most general use is of the Cyclone type, and is ordi- 
narily styled on the market the Vermorel nozzle. This will prove very 
satisfactory, particularly for smaller trees, and is the one commonly 
supplied with the knapsack sprayers. The Nixon nozzle, which is 
supplied only with the Nixon pumps, is a very serviceable one, and 
particularly advantageous for use with large trees. 
The Gas Treatment.—This method has not been extensively used in 
California against this insect, but has been used with very considerable 
success against the so-called Red Scale upon orange and lemon trees. 
It is an expensive operation, but is unquestionably more thorough 
than spraying. Trees infested with different kinds of Aspidiotus have 
been entirely freed by a single application of this gas. 
The treatment consistsin enveloping the tree in an air-tight tent 
and afterwards fillmg the tent with hydrocyanic acid gas, generated 
from fused potassium cyanide, sulphuric acid, and water. This gas is 
much lighter than air and as soon as generated rapidly rises and fills 
the tent. It is of course fatal to all forms of animal life, and care must 
be exercised in using this treatment. The tent is usually constructed 
in the form of an octagonal sheet, of what is ordinarily known as 
8-ounce duck, and is afterwards oiled with boiled linseed oil. A tent 
of this kind measuring 40 feet in diameter will cost about $50, and 
other sizes in like proportion. Almost any glazed earthenware vessel 
will answer the purpose of a generator. The potassium cyanide used 
is usually of 60 per cent strength and the sulphuric acid is of the ordi- 
nary commercial brand. The proportions are, 1 ounce by weight of 
the cyanide, i fluid ounce of the acid, and 3 fluid ounces of water. 
This is sufficient for 150 cubic feet of space inclosed by the tent. 
The water is first placed in the generator, the acid added, and after 
the generator is placed under the tent the cyanide is added to the solu- 
