A. H. Lees 249 



stiiicd and filtered through ;i sieve with L6 meshes to the inch into 

 the spraying machine. 



Lastly the potassium dichromate previously dissolved in a small 

 quantity of water is poured into the machine and stirred up. The 

 mixture is then ready for application. 



Where the lime is very good the amount might be reduced to 25 lbs 

 as 30 lbs of good lime sometimes makes the mixture too thick for easy 

 straining. It is important to soak glue first in cold water as a direct 

 application of hot leads to the formation of intractable lumps. Where 

 it is desired to avoid the use of hot water, as in continuous spraying, 

 the following procedure may be adopted. 



One lot of lime is slaked with water and allowed to cool as above 

 described. Then a second lot is made up and by means of the heat 

 evolved the glue for the first lot can be dissolved by standing the pail 

 of soaked glue in the hot lime. It only needs a temperature of about 

 100° F. to dissolve glue that has been previously soaked and this is 

 easily obtained by this method. 



This lime-glue-dichromate mixture has been tried against ordinary 

 lime-wash at Long Ashton and has given decidedly superior results. 

 An application to an apple tree stopped aphis hatching to such an extent 

 that hardly an aphis was to be seen on it throughout the season though 

 control trees were very badly attacked. The tree stood out all the 

 season from its fellows by the healthy green uncurled leaves and at 

 the end of the season by its very numerous well-developed fruit buds. 



Hide glue can be obtained in hundredweight quantities at i\d. a 

 pound so that the cost of the spray per 10 gallons works out as follows : 



s. d. 

 Lime 30 lbs @ Is. per cwt 3 



Glue 2 lbs @ 4|d 9 



Potassium dichromate § oz. @ 6d. per lb. ... } 



Total 1 0{ 



giving an approximate cost of l|d. per gallon. 



