EXPERIMENTS ON THE APPLE WITH SOME NEW FUNGICIDES. 7 



Plat 4, gypsum Bordeaux mixture. — This was prepared in the same 

 manner as the spray for plat 3, 3-3-50 Bordeaux mixture being made 

 up and 3 pounds of gypsum mixed with 6 or 8 gallons of water added 

 in filling the barrel. No change in color resulted. 



Plat 5, neutral Bordeaux mixture. — This spray was made in the same 

 manner as standard Bordeaux mixture, except that a very small 

 quantity of lime was used and an excess of bluestone in running the 

 materials into the barrel. With the excess of bluestone, blue litmus 

 paper is turned red. Lime was cautiously added until no marked 

 change was produced in either the blue or the red litmus paper. 



Plat 6, self-boiled lime-sulphur. — In these experiments, the rather 

 strong 10-10-50 self-boiled lime-sulphur was purposely used, so 

 that if spray injury resulted it would occur at its worst. In mak- 

 ing up the iron sulphid and the copper sulphid mixtures, therefore, 

 the same formula of 10-10-50 was used. In commercial work, how- 

 ever, the 8-8-50 formula should be used. 



Briefly stated, this mixture is made up as follows : 



In a barrel holding 50 gallons place 8 pounds of good stone lime. 

 Pour over this enough water to nearly cover it. As the lime begins 

 to slake, dump in the sulphur. This should preferably be run 

 through a screen, to break up lumps, and mixed with water to the 

 consistency of a slush. Stir the sulphur into the slaking lime 

 with a strong paddle and add water enough to keep the lime from 

 burning and to keep the mixture in a slushy condition. The stirring 

 should continue occasionally until the greater portion of the lime is 

 slaked into a cream or paste. Meantime the barrel should be cov- 

 ered with burlap sacks or a piece of old carpet or otherwise pro- 

 tected to retain the heat. At the end of fifteen or twenty minutes 

 the lime will be found to be thoroughly slaked and the sulphur partly 

 combined with it. Considerable brown discoloration shows the extent 

 of the chemical combination. The mixture is then diluted, first 

 with a small quantit}^ of water stirred in with a paddle and then 

 sufficiently to fill the barrel to the 50-gallon mark. Space is left 

 before finishing to add the 2 pounds of arsenate of lead, stirred in, in 

 the form of milk, in 2 or 3 gallons of water. 



Plat 7, copper-sulpliid mixture, No. 1. — To make this spray the 

 self-boiled lime-sulphur, already described (10-10-50), was used as a 

 basis. Space was left to add 2 pounds of copper sulphate in solu- 

 tion, diluted with about 6 or 8 gallons of water. This turned the 

 mass a decidedly bright reddish brown color as it was stirred 

 into the mixture. On the addition of 2 pounds of arsenate of lead, 

 previously mixed with water into a milk, no additional change in 

 color was apparent. This may have been due to inability to detect 



[Cir. 58] 



