196 On Sulphuric Acid and Naphthaline. 1826.] 



well known, were adopted for the purpose of obtaining accu- 

 rate results. When operated upon in this way, the only sub- 

 stances evolved from the salt were carbonic acid and water. 

 As an instance of the results, 3*5 grains of the salt afforded 

 1 1 P 74 cubic inches of carbonic acid gas, and 0*9 of a grain of 

 water. The mean of several experiments gave 32'93 cubic 

 inches of carbonic acid gas, and 2*589 grains of water for every 

 10 grains of salt decomposed. 



On these data, 100 grains of the salt would yield 329*3 cubic 

 inches of carbonic acid, or 153*46 grains, equivalent to 41*9 

 grains of carbon, and 25*89 grains of water, equivalent to 2*877 

 grains of hydrogen. Hence 100 grains of the salt yielded 



Baryta .... 27-57 ... 78 



Sulphuric acid . . 30'17 . . . 85*35 



Carbon .... 41*90 ... 118*54 



Hydrogen . . . . 2*877 . . . 8*13 



102*517 



In the second numerical column the experimental results are 

 repeated, but increased, that baryta might be taken in the 

 quantity representing one proportional, hydrogen being unity ; 

 and it will be seen that they do not differ far from the following 

 theoretical statement : 



Baryta ... 1 proportional . . 78 



Sulphuric acid . 2 ditto . . 80 



Carbon .... 20 ditto . .120 



Hydrogen ... 8 ditto . . 8 



The quantity of sulphuric acid differs most importantly from 

 the theoretical statement, and it probably is that element of the 

 salt in the determination of which most errors are involved. 

 The quantity of oxide of copper and of acids required to be 

 used in that part of the analysis, may have introduced errors, 

 affecting the small quantity cf salt employed, which when mul- 

 tiplied, as in the deduction of the numbers above relative to 

 100 parts, may have created an error of that amount. 



As there is no reason to suppose that during the combination 

 of the acid with the baryta any change in its proportions takes 

 place, the results above, minus the baryta, will represent its 

 composition: from which it would appear, that one proper- 



