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for application to plants to correct tlie 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 case in 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 imjirovement 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 i)resent 

 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 

 enuilsiou 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 



