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'Carded. Accepting these practical tests under all kinds of 

 •conditions as a fair standard for determining efficiency, we 

 must conclude that the lime-sulfur wash still stands as the 

 best remedy for controlling San Jose scale. There is no 

 doubt as to the value of the home-boiled mixture. It has 

 given excellent results under a great variety of conditions. 

 The more recent Cordley formula* is coming to the front in 

 a most promising manner, while the standard commercial 

 preparations appear to be equally satisfactory. There is 

 still some question as to which formula is the most econom- 

 ical and can be relied upon in the long run to give the best 

 results. The desirability of making some modifications 

 while important, should not prevent the employment of 

 the standard lime-sulfur washes. One can hardly err if 

 he uses a good lime-sulfur wash and makes a thorough ap- 

 plication. 



A word as to materials. Experience has shown that 

 the powdered commercial sulfur, 99.5 per cent, pure is as 

 •efficacious as the more costly though finer, sublimed flowers 

 • of sulfur. It is advisable to use a pure lime, 90 per cent, 

 calcium oxide and thus escape trouble with sediment. Mag- 

 nesium lime is unsatisfactory, since the oxide does not com- 

 bine readily with sulfur to form efficacious sulfides similar 

 to those of the lime-sulfur wash. The presence of quan- 

 tities of magnesium lime is indicated by the giving off, dur- 

 ing the process of boiling, of hydrogen sulfid, a somewhat 

 -poisonous gas having an odor similar to that of rotten eggs. 

 Commercial lime-sulfur washes should not be purchased un- 

 less accompanied by a guaranty and should give a Beaume 

 -reading of about 33 per cent. Such a wash may be diluted 

 with 8 parts of water. Recent experiments have shown 

 that the sediment found in some of these commercial washes 



♦This wash may be prepared by slaking 60 lbs. of good lime 

 in a small quantity of water in a 75 gal. cooking vessel and stir- 

 ring in 125 lbs. of sulfur previously made into a paste; then add 

 45 gals, of water and boil rapidly for one or two hours or till 

 practically all the sediment has disappeared; dilute to 50 gals, 



'The clear liquid should test 25° on the Beaume scale. This wash 

 may be kept indefinitely, and just prior to application it should 

 be diluted with 5 1-2 times its volume of water or till the diluted 

 mixture gives a reading on the Beaume scale of about 4 1-2°. It 

 is also well to add at this time, without increasing the dilution, the 

 soluble portion of 6 lbs. of good stone lime in the form of milk 



4)f lime for each 50 gallons of spray. 



