SPRAYING NOTES FOR 1904-1905. 65 
Bordeaux mixture may be made from these stock solutions 
in various ways. ‘The best mixture may be made by using an 
arrangement somewhat like that seen in cut. 
Place two wooden cisterns, or barrels, on a platform so that 
their bottoms will be higher than the spray tank or barrel to be 
filled. If a 40-gallon spray barrel is to be used stir thoroughly 
the stock solution of copper sulphate and put 2 gallons of the 
solution (4 pounds copper sulphate) into one of the tanks, and 
_add water to nearly 20 gallons. In the other tank put an equal 
amount of lime solution, and add water to nearly 20 gallons. 
Draw off the contents of both tanks through a 20 or 30 mesh 
copper strainer into the spray tank. Do not use a strainer 
made from cloth, as the fibres of the cloth clog the spray 
nozzles. 
After the material is in the spray tank stir thoroughly, then 
dip out a small amount and test for unprecipitated copper sul- 
phate by pouring in a few drops of a solution of ferrocyanide of 
potassium dissolved in water. If a dark brown coloration 
results, more lime is needed. 
If the lime used in making. the original solution is good, less 
than 4 pounds of it to 2 gallons of water will suffice; but an 
excess of lime does no harm and may prevent trouble. 
Use nothing but wood, brass or copper, and rubber for 
spraying apparatus. Iron in the pump or connections is not 
only quickly eaten by the copper sulphate, but it forms scales 
that cause trouble by clogging the nozzles. The same difficulty 
will arise if the pump-hose, nozzles, and tank are not thoroughly 
washed every time after being used. 
