THE PAINTED APPLE MOTH. 99 



and therefore poisoning the food is the most effectual 

 method of dealing with these, no matter how great the 

 numbers which are attacking the trees ; and for the benefit 

 of any person wishing to prepare this class of poison for 

 the sake of cheapness, I give the formula as recommended 

 by my colleague, Mr. A. N. Pearson, Government Agri- 

 cultural Chemist for Victoria. 



" In an earthenware jar dissolve 2h lbs. of sulphate 

 of copper (bluestone) in 1 gallon of water. In another 

 vessel dissolve 1 lb. of white arsenic (or 1^ lbs. of crude 

 arsenic from pyrites works) and 5 lbs. of common wash- 

 ing soda in 5 gallons of hot water, stirring occasionally 

 until all the arsenic is dissolved. Keep the two solutions 

 separate until required for use, then mix them in the pro- 

 portion of one of the copper solution to five of the arsenic, 

 and the resulting mixture, being diluted with from 45 to 

 60 times its quantity of water, is ready for the spray. 

 Thus, the 1 gallon of bluestone solution and 5 gallons of 

 arsenic solution, when mixed together, will produce 6 

 gallons of Paris Green mixture, which, being diluted, will 

 produce 276 gallons of strong or 366 gallons of weak 

 material for the spray." 



As a combination mixture for the purpose of spraying, 

 Mr. Mc Alpine recommends the following, and says — 

 " Either of the above forms (alluding to various forms of 

 the Bordeaux mixture) can be used as a combined in- 

 secticide and fungicide with Paris Green or London 

 Purple. The soluble arsenic in these substances is 

 rendered insoluble by the action of the lime, and thus 

 is not injurious to the green parts of plants. About 1 lb. 

 of Paris Green added to 200 gallons of the Bordeaux 

 mixture is found to be a safe combination." 



We have also other materials at our disposal, as 

 hellebore, quassia chips, &c., &c., all of which have been 

 alluded to in Part II., but in the case of the present 

 insect the use of these is hardly necessary. 



