New York Agricultural Experiment Station. 229 



would be more convenient than the ordinary stock solution as 

 there would be no necessity of weighing the copper sulphate or 

 of measuring the water. This gentleman has followed this plan 

 for two seasons with good results. However this method can 

 only be commended to careful men who will take pains to see 

 that the solution is always a saturated one. A large vessel of 

 cold water is provided in which is suspended a large amount of 

 copper sulphate, more than the water can possibly take up. This 

 should be prepared at least a day before the solution is wanted 

 for use in order that the sulphate may have time to dissolve. 

 As the solution is taken out more water should be added to the 

 vessel from time to time and copper sulphate should be con- 

 stantly kept in suspension. By exercising a due amount of care 

 a fairly even solution may be maintained. One gallon of water 

 at ordinary temperature, 59° F., will dissolve 49 ounces of copper 

 iulphate. Therefore one and one-third gallons of such a solu- 

 tion will contain the required four pounds of copper sulphate 

 for a barrel of Bordeaux mixture. 



Bordeaux mixture should be used soon after it is made, or 

 at least on the same day that it is made, as it soon begins to 

 deteriorate in value. 



Kerosene anuJsion. — Kerosene emulsion is made by dissolving 

 one-half pound of common soap or whale oil soap in one gallon 

 of soft water. Heat the mixture, and when boiling hot remove 

 it from near the fire and add it to two gallons of kerosene. The 

 whole is now thoroughly mixed by pumping continuously through 

 a small force pump for about five minutes. Mix until the ingre- 

 dients form a creamy mass that becomes thick when cool and 

 from which the oil does not separate. When using on foliage 

 dilute with from ten to fifteen parts of water; when used as a 

 winter treatment it may be applied as strong as one part of the 

 mixture to four parts of water. After the stock emulsion be- 

 comes cold it hardens so that it is necessary to melt it before it 

 can be successfully diluted. It takes fire very readily, so it is 

 always a safe plan to have a fire out of doors when making the 

 emulsion. This emulsion is used to kill insects that have sucking 

 mouth parts; it is not a poison but kills by contact. 



