THIRTHIIXTH ANXl'AL MEETING. 89 



Prof. liRirrox : ( )iir hands. Of course, on a large scale it 

 might be necessary to devise some apparatus, but we were 

 making" up only a barrel at a time. We put warm water in the 

 pail and threw in four or five pounds of sulphur, — it takes 

 perhaps fifteen minutes to mix 14 pounds of sulphur, — then we 

 put it into the barrel with the lime and slaked the lime, stirring 

 it to make sure it was thoroughly slaked. We added water to 

 make the barrel perhaps a third-part full, turned on steam wath 

 the rub1)er hose, and boiled it for thirty n\inutes. The sulphur 

 was all dissolved and there was very little sediment, but we 

 strained it into our spraying-barrel and filled the barrel up, 

 diluting with water, then applied it at once to the trees. We 

 had a very heavy rain Sunday morning; this spraying was 

 done Thursday and Friday, but, so far as I can see, the trees 

 are just as wdiite as the day after it was applied, and it has 

 adhered very nicely to the trees and appears to be killing the 

 scale all right. 



Question : A thirty minutes boil ? 



Prof. Brittox : Yes, sir. We didn't make any chemical test, 

 but I believe all the sulphur was dissolved ; we got a very dark- 

 colored liquid. It should be nearly all dissolved. 



[At this point Prof. Britton exhibited specimens of caustic 

 soda in glass jars.] 



This caustic soda may contain a little carbonate, but you 

 can't afford to buy a chemically pure article. In this case 

 I ordered soda 78 per cent. pure. They wrote that they could 

 send me 74 per cent, instead of 78, and on the bill it was 

 marked 98 per cent., and I don't know which we got. 



]Mr. Stoxe: Where did you get it? 



Prof. Britton : Through the General Chemical Company 

 of Xew York City. They had it shipped from the Thomsen 

 Chemical Co., of Baltimore. It is certainly a cheap material, 

 and I believe it is worth further trial. It has one advantage, 

 the ability to cover a tree with it very readily. It comes next 

 to the oils in that respect. 



Mr. Stone: How long ago did you use that? 



Prof. Britton: In March, 1901. 



Mr. Stone: W'hy did you not use that instead of the lime 

 and sulphur? 



