EXPERIMENTS ON ORANGE SCALE-INSECTS. 21 
the time required to bring supplies is nearly as much as to make the 
application. Another hand was an increase of final cost. A horse and 
cart require time and attention, and the horse is idle eight-tenths of the 
time. 
System 4. — I obtained one of the Dudley garden engines, which meets 
to a great extent the requirements of a majority of cases. 
The reservoir contains seven and a half gallons, the pump is firmly 
fixed to the reservoir, which in use stands on the ground ; for moving 
it is lifted by a lever and supported on a wheel truck, the tubing and 
nozzles attached as before. This implement is a very great conven- 
ience. 
Although two men can do more working together than separately 
with this system, two are not as necessary as with the aquajet. The 
stability of the pump without holding, gives freedom of motion for 
change of position. The large quantity held in the reservoir saves 
time, and the truck makes moving easy, so that one man can easily 
and conveniently work unassisted. The wheels of the engine truck are 
too small for plowed grounds. 
System 5. — Placing the engine in a cart, with a further supply of 
solution in a barrel, driving up close to the tree, then standing in the 
cart, the pump can be worked and the spray directed to the exterior of 
the tree, driving around as required to reach all sides, is the simplest 
and most satisfactory method of spraying orange trees on a large scale 
with appliances now in market, and suggests — 
System 6. — For large groves of large trees place a kerosene barrel, 
with a good force pump firmly attached to one head, in a cart. A light 
derrick fixed to the cart, carrying a light, strong rod twenty or more 
feet in length, supports nozzles at certain distances, to form a continu- 
ous sheet of spray of sufficient volume that the tree will be thoroughly 
sprayed on its exterior by driving around near it whilst the pomp is 
being worked. 
The interior of the tree is sprayed at another time, by a cluster of 
cyclone nozzles, or a conical cyclone nozzle. 
A cart-tank might be preferred, but the system suggested enables 
the cart to be used for other purposes, and the pump and reservoir to 
be carefully housed. 
The particular make and sizes of implements used are only typical ; 
any similar arrangement used in the same way should produce like re- 
Stilts. 
The method of proceeding has been to note the extent o\' apparent 
damage done by the insect, condition of uninfested portion oi the tree. 
if any, the condition of surrounding trees, if cultivated, if fertilised) 
character of soil, position on high or low land. Examining the scales 
with a lens, noting the variety, if parasitized, if larva* arc running about, 
then turning over the scales to see if eggs are present. Taking a fair 
sample for home examination, then applying the solution o( a known 
strength. 
