Mr. C. Binks o?t Electricity, 135 



And by 1'6344<7 for the quantity of sulphate of barytes 

 which it produces by precipitation. 

 2. To find the weight of the components and equivalents 

 of any quantity of sulphate of potash, multiply it 

 by 0'449019 for the potassium it contains. 



0*550981 for the sulphur and oxygen. 

 0-54067 for the potash. 

 0*45933 for the sulphuric acid. 

 And by 1*33633 for the quantity of sulphate of barytes 

 which it produces by precipitation. 

 Example. — In the analysis of a sample of commercial alum, 

 we have proceeded so far as to have nothing to separate but 

 sulphate of potash from sulphate of soda, both of which 

 alkalies have been detected by previous testing. 



a. The mixture of sulphates weighs 7 grains. 



b. It produces by precipitation 10*54687 grains of sulphate 



of barytes. 



c. The weight of the mixture a, 7 grains, multiplied by 



1*33633 gives 9*35431. 



d. 9*35431 subtracted from 10*54687 gives 1*19256. 



e. 1*19256 divided by 0*29814 gives 4. 



f. The weight of the sulphate of soda in the mixture a is 4 



grains. 



g. The weight of the sulphate of potash is 3 grains. 



The quantity of sodium equivalent to the sulphate of soda, 

 is 4x0*326095 



The equivalent of soda, is j • • • 4x0*43819 



The quantity of potassium equivalent to the sulphate of 

 potash, is 3x0*449019 



The equivalent of potash, is 3 x 0*54067 



The atomic weights employed in these calculations are 

 those of Berzelius. 

 Glasgow, March 19, 1838. 



XIX. On some of the Phcenomena andLaws of Action of Voltaic 

 Electricity, and on the Construction of Voltaic Batteries, 

 Sfc. By Christopher Binks. A second Communication, 

 addressed to J. F. Daniell, Esq. F.R.S., Sfc, Professor of 

 Chemistry in King^s College, London. Part the Second. 



[Continued from Part i. p. 75.] 



Section IV. 

 73. nPHE ultimate object of the following experiments is to 

 -*■ determine on the most advantageous construction of 

 the voltaic battery ; that is, such a construction as shall com- 



