[ 253 J' 



N APPEND! X, 



Containing an account of fome experiments 

 made by Mr. Hey, which prove that there 

 is no oil of vitriol in water impregnated 

 with fixed air extracted from chalk by oil 

 of vitriol ; and alfo a letter from Mr. Hey, to 

 Dr. Prieftley, concerning the effects of 

 fixed air applied by way of clyfter. 



Experiments to prove that there is no 

 oil of vitriol in water impregnated 



WITH FIXED AlR. 



It having been jfuggefled, that air arifing from 

 a fermenting mixture of' chalk and oil of vitriol 

 might carry up with it a fmali portion of the 

 vitriolic acid, rendered volatile by the a£t of fer- 

 mentation ; I made the following experiments, in: 

 order to difcover whether the acidulous tafte, 

 w 7 hich water impregnated with fuch air affords, 

 was owing to the prefence of any acid, or only to 

 the fixed air it had abforbed. 



Experiment I. 



I' mixed a tea-fpoonful of fyrup of violets with 

 ail ounce of diftilled water, . faturated with fixed 

 air procured from chalk by means of the vitriolic 

 acid ;- but neither upon the firft mixture, nor after 



a*. (landing: 





