f)G . APPARATUS FOR THE ANALYSIS OF GASSES. 



Experiments ^n example of the analysis of a highly combustible spe-» 

 ' cies of elastic fluid is furnished by the following experiment* 

 on the olefiant gas, obtained from alcohol and sulphuric 

 acid. Of this gas 100 cubic inches, at a mean of the baro-> 

 meter and thermometer, were equal to 30 troy grains; hence 

 its specific gravity was 967. 



In the receiver o 0, were contained of this gas 6*3 cub. in* 

 Residue , . . . . 2 



Gas consumed • • 4*3 



In the receiver b, were 43*4 inches of oxigen gas. After 

 the combustion, there remained 38*2 cubic inches of mixed 

 gasses, of which 8*6 were carbonic acid. None of the in- 

 flammable gas, which passed through the bent tube, had 

 escaped being burned, for the quantity of gas in b, not ab- 

 sorbable by sulphuret of lime, so far from having been in- 

 creased, was found to have sustained a trifling diminution. 

 The oxigen gas, which was consumed, amounted to 13*8 

 cubic inches. Reducing these results to centesimal propor- 

 tion, 100 cubic inches of this gas would give 200 of carbon 

 nic acid, and absorb 325 of oxigen gas. This experiment 

 agrees with Mr. Dalton's, as to the proportion of carbonic 

 acid from the combustion of olefiant gas, but assigns a 

 larger consumption of oxigen. It may be observed, how- 

 ever, that the specific gravity of the gas, which I employed, 

 exceeded a little the statement of the Dutch chemists, who 

 found its specific gravity to be 909, common air being 1000. 

 Gasses from Having satisfied myself, by repeated experiments, of the 



Tegetable sub- accuraC y f the results which may be thus obtaiued, I pro- 

 ceeded to the combustion of the gasses from a variety of 

 vegetable substances, and especially from those which it 

 seemed probable might become economical sources of light. 

 In the present memoir, I shall describe those only, which 

 were made on coal and a few similar substances, reserving 

 the rest for a future communication. 



Gas from cannel coah 



Gas from can- This was received in two separate portions. Of the first 

 »ei coal. product, 100 cubic inches, corrected to a mean temperature' 



and 



