326 Report of the Horticultural Department of the 



dcrstanding of the subject the simple method of weighing and mixing 

 the ingredients will first be presented. 



Bordeaux Mixture, i-io Formula. 



(To make 50 gals.) 



Copper sulphate (blue vitriol) 5 pounds. 



Quicklime (not slaked) 3 'i to 5 pounds. 



Water 50 gallons. 



1. Dissolve the 5 lbs: of copper sulphate in any convenient way, in 

 either hot or cold water, using some vessel which the copper sulphate 

 will not corrode. It does not corrode wood, brass or porcelain but 

 acts quickly on iron. Dilute the copper sulphate solution to half or 

 two-thirds of the 50 gallons. 



2. Slake the lime and dilute with the remaining part of the 50 gal- 

 lons of water. It is an advantage to strain the milk of lime to exclude 

 particles which might clog nozzles. 



3. Pour the two ingredients together after being thus diluted. It 

 is important not to mix the lime and copper sulphate solution till after 

 diluting them as much as the formula permits. If mixed in concen- 

 trated form the solid particles of the resulting bordeaux mixture do 

 not stay in suspension well. When the particles hold up well the 

 mixture is better carried for heavy poisons, such as paris green, which 

 may be added for killing insects. Also, such a mixture may be more 

 uniformly distributed than one containing heavier particles. How 

 much less rapidly bordeaux mixture settles when prepared in the im- 

 proved way, which may be called the new way, than it does when 

 made by mixing concentrated ingredients in the old way will be seen 

 at once by comparing A and B in Figs, i, 2 and 3, A having been 

 made by mixing concentrated solutions and B by mixing dilute solu- 

 tions. Fig. I shows the mixture just made and Figs. 2 and 3 the 

 same mixtures 20 minutes and one hour later, respectively, 



Bordeaux mixture made from stock solutions. — Where large areas 

 are to be sprayed it is convenient to make the bordeaux mixture from 



