LABORATORY MANUAL OF HORTICULTURE 



Baume 35 is .318 ; this, divided by the decimal for Baume 20, 

 which is .160, will give 19.8, or the number of dilutions required, 

 this result being obtained by adding 19.8 volumes of water to 1 

 volume of the concentrated lime and sulphur. This rule is based 

 upon the general fact that the density of a solution heavier than 

 water varies inversely with the number of dilutions. 



When the density of the lime-sulphur solution or the home- 

 made wash has been first determined by the use of a hydrom- 

 eter, sprays of any desired density may be calculated by using 

 the table. The rule for determining the number of dilutions is 

 as follows: divide the decimal of the concentrate by the deci- 

 mal of the spray desired ; the quotient will be the number of 

 dilutions. 



Decimal of the concentrate 



'Decimal of the spray desired 

 .318 



= the number of dilutions 

 = 19.8 



.160 



Example 2. Assuming that the decimal of the concentrate is 

 known and that this concentrate is diluted by a certain number 

 of volumes of water, what is the decimal of the spray ? Taking 

 the same example as in Ex. 1, we have the decimal of the con- 

 centrate, .318, and the number of dilutions, 19.8. Dividing .318 

 by 19.8 equals .160, which is the decimal of the spray and cor- 

 responds to 20 Baume. Now figure out the degree of dilution 

 for each sample you make in the laboratory. 



Decimal of the concentrate 



Number of dilutions 



.318 



= decimal of the spray 

 = .160 



19.8 



Secure some concentrated lime-sulphur solution. How does 

 this differ in color and looks from the home-made lime-sulphur 

 solution ? Test each of the solutions with the hydrometer. Note 

 the reading in each case. What amount of water was necessary 

 to bring both of the solutions to the same reading ? How do you 

 account for the difference, if any ? Discuss fully. 



REFERENCES : 



Bulletin No. 288, Cornell Agricultural Experiment Station. 

 Bulletin No. 289, Cornell Agricultural Experiment Station. 

 Circular No. 10, Michigan Agricultural Experiment Station. 

 Bulletin No. 330, New York Agricultural Experiment Station. 



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