THE IMPORTANT TUNGICIDES 19 



liquid. This operation washes the carbonate free of 

 most of the sodium sulphate which contaminates it. 

 Make a filter of stout muslin, by tacking the same to a 

 square wooden frame which w411 just fit over the open 

 top of the second barrel, letting the muslin hang down 

 loosely so as to form a sack ; through this filter the pre- 

 cipitate, so as to drain off the excess of water, and as the 

 filter fills remove the precipitate, and allow it to dry in 

 the air, when it is ready for use. The operation is not 

 troublesome, and can be carried on in connection with 

 other work." 



Potassium Sulphide. — Dissolve one-half ounce 

 of potassium sulphide (liver of sulphur) in one gallon of 

 hot water. When cold aj^ply in a spray. Used to pre- 

 vent gooseberry mildew and similar diseases. Commer- 

 cial liver of sulphur costs fifteen to twenty cents per 

 pound. 



Soda Hyposulphite. — Dissolve one-half ounce, or 

 one ounce of soda hyposulphite in ten gallons of water. 

 This is recommended by some for gooseberry mildew 

 and apple scab, but it is not in general use. 



Sulphate of Copper. — Besides its use in combi- 

 nation with other substance, copper sulphate is often 

 applied to vines and trees early in spring to destroy the 

 winter spores of fungi. For this purpose it is used in a 

 simple solution made by dissolving two pounds of the 

 cojDper sulphate in fifty gallons of water. 



Copper Chloride. — This is .-a, greenish crystalline 

 salt of copper, readily soluble in water, which has been 

 recently tested as a fungicide at the Cornell University 

 Experiment Station, with encouraging results. It is 

 said to cost, at retail, about ten cents an ounce, or fifty 

 cents a pound. Used at the rate of one and one-half 

 ounces to twenty-two gallons of water it injured jieach 

 and apple foliage. So little is now known of it that no 

 practical recommendations can here be made, other than 

 that it is worth experimenting with. 



