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a large quantity can be emulsified as rapidly as a smaller quantity, and 
violent agitation through a spray-nozzle at a temperature of 100°, and 
as frequently described in my reports, gives the quickest results. 
Take, for instance, the mixture recommended by your county board 
of horticultural commissioners. You will find that with the soap and 
wood-potash there are twenty-five parts of the diluent to one of the kero- 
sene recommended, and there is every reason to believe that the kerosene- 
in this wash might just as well be thrown away, and that it adds com- 
paratively little, if any, to the efficiency of the wash, at least for the 
fluted scale. If, on the contrary, we could add to the ordinary emul- 
sion any materials that would give greater adhesiveness, such an addi- 
tion will prove an advantage. Such we get, to some extent, in the 
soap emulsion, for which reason it has a slight advantage over the milk 
emulsion. And after examining the trees treated with resin washes, I 
am strongly inclined to recommend that these resin washes be used as 
the diluent to the soap emulsion made after the usual formula. Some- 
thing similar was tried some years ago by one of my agents in Florida, 
Mr. Joseph Yoyle, who used fir balsam in place of resin, in connection 
with the oil emulsion, and obtained most satisfactory results. A cer- 
tain amount of dextrine, or, yet better, flour, if mixed with the wash, 
would prove valuable for the same purpose. 
Again, if permanency can be given to the effect of a wash so that 
the few insects escaping the first application, or which would hatch out 
thereafter, would succumb, such addition would be invaluable $ and 
though the arsenites are, as a rule, effective chiefly against mandibu- 
late insects, or those which masticate their food (in other words, 
although the action of these poisons is mainly through the stomach), 
yet I happen to know from experience that they have also a direct 
effect by contact. Therefore I recommend, with considerable confi- 
dence, that in this dilute kerosene emulsion there be added a small 
proportion of arsenious acid, say from 2 to to 3 ounces to every 50 gal- 
lons of wash. This arsenious acid may be prepared and added in va- 
rious ways. Probably one of the simplest would be to take half a 
pound of arsenic to half a pound of sal-soda, boil this in one-half gal- 
lon of water until the arsenic is dissolved, and mix this with about 100 
gallons of the diluted emulsion. A quarter of a pound of London pur- 
ple to 50 gallons of the diluted emulsion, or even a still greater amount, 
would, perhaps, serve the same purpose and be less likely to injure the 
tree. 
I am aware of the danger of making recommendations that have not 
yet had thorough trial, but I have already made a few limited experi- 
ments (and intend making more) which would seem to justify these, and 
at all events if care be taken not to use too large a quantity of the ar- 
senic no harm will result from it, either to the tree or to those who use 
the fruit. 
