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for application to plants to correct the injuries from fungi and insects 
of various sorts at one treatment is not by any means new. The Cor- 
nell combination of Bordeaux mixture with kerosene-soap emulsion and 
Paris green is a casein point. Mr. Slingerland, who tried this combi- 
nation, does not give it an altogether satisfactory indorsement. That 
the Bordeaux mixture and the kerosene emulsion may be easily com- 
bined is to be expected, from the fact that lime is a well-known emul- 
sifying agent for oils; and Mr. Slingerland's experience and my own 
have shown that the combination results in a certain improvement of 
the Bordeaux mixture in holding the lime in suspension, and that there 
is no separation of oil even when the lime is used in very excessive 
quantity. In conjunction with Mr. Waite, of the Division of Vegetable 
Pathology in the Department of Agriculture, a number of pear trees 
were treated with a combination mixture of Bordeaux and milk emul- 
sion. The treatment was made July 25, and the trees at the present 
time are still covered with the Bordeaux, in spite of the fact that sev- 
eral very hard rains have washed them since the application. This 
seems to show that this mixture, at any rate, adheres almost as well as 
the Bordeaux alone, though perhaps not having quite the same tenac- 
ity. Experiments were made in combining both the whale-oil soap 
emulsion and milk emulsion with (1) Bordeaux, to which just enough 
lime had been added to neutralize the copper, and (2) in which a slight 
excess of lime had been used, and (3) to which a very great excess of 
lime had been added. The mixture was equally satisfactory with the 
emulsions of both milk and soap in all three of the Bordeaux mixtures. 
With the soap emulsion mixtures, after over a week's standing, a very 
slight trace of free oil appeared on the top of the jars strongest in 
lime. 
In view of the fact that ordinary hard waters, or those containing 
much lime or magnesia, will, when used in making emulsions, liberate 
the free oil on account of the combination of soap with the lime, it 
would seem that the soap emulsion could not be satisfactorily used with 
the Bordeaux mixture, but experiments have shown that this is not 
the case. This is easily explained when it is remembered that it is the 
lime in solution in the water which is the liberating agent, whereas in 
the Bordeaux mixture the lime in suspension is really an emulsifier, 
and counteracts the effects of the dissolved lime in the liquid. The 
use of Paris green or London purple in a mixture of this sort has no 
effect upon the stability of the combination. It seems to me, therefore, 
perfectly feasible to apply a combination of Bordeaux mixture and 
emulsion to plants, and there are a number of cases where such appli- 
cations would be desirable. The pear-tree Psylla may be effectively 
treated with kerosene emulsion in early spring, just after the leaves 
have unfolded and the eggs have hatched, and at the same period the 
application of Bordeaux mixture is customarily made to guard against 
the blight, The combined mixture could be applied with scarcely any 
