

£30 0N TIIE QUANTITY. OF CARBON IN CARBONIC ACID 



Then, to find how much carbonic acid was contained in 

 these 2T06 cubic inches, we state it thus: As the total quan- 

 tity of gas after the experiment is to the total weight of car- 

 bonic acid gas found by calculation, so is the quantity of gas 

 experimented upon to the weight of carbonic acid gas which 

 it ought to have contained, 



51*20 : 13<)1 : : 21*06 : 5*72 grains. 



Every 100 grains of precipitated carbonate of lime con- 

 tain 44 grains of [carbonic acid; 12 grains were procured in 

 our experiment. 100 : 44 : : 12 : 5*28 



The weight of Therefore the carbonic acid contained in our precipitate of 

 Mwee<nwlT C l * *'6™°* wei g ned 5*28; by calculation it should have 

 with the fore- weighed 5*72; this is as near as we had a right to expect 

 going results. from the difficulty of collecting the precipitate. 



Stone Coal. 



Experiment Upon the suggestion of our mutual friend Professor Davy, 



with Welch we next examined the results of the combustion of stone 

 stone coal. coa j an( j pi um bago ; thermometer 57° Fahrenheit, barome- 

 ter 29*65. 



The stone coal from Wales, employed by maltsters, is well 

 known to contain little or no maltha, or mineral pitch, and 

 to burn without flame. . 



A portion of this coal was placed under sand in a crucible, 

 4 grs. charred an( ^ ex P ose( l to a strong heat for one hour ; 4 grains of it thus 

 and then bum- prepared were put into the tray : our oxigen left a residuum of 

 5 parts in 100, and we began with 49*84 cubic inches as 

 usual. The tray being placed in the platina tube was 

 heated to redness for about 10 minutes. When the gas 

 was first passed, we thought we saw a flash in the glass 

 tubes. On suffering the whole to cool, the quantity of gas 

 still remained the same, and the tray being drawn out con- 

 tained only *5 of a grain unconsumed. From the gas thus 

 |gr. residuum, charged with 3*5 grains of coal, 



Residual gas Lime water absorbed 53 parts from 100. 



increased '03 , The tests for oxigen 39 



Residuum 8 or an increase of 3. 



100 



Cor recti ou 



