Chap. 6.] A-cdous Fermentation. 69 



fluid called etber, extremely volatile, and alfo of a 

 pleafant odour: this comes over as foon as the fluid 

 in the retort begins to boil, and the upper part of the 

 receiver is at the fame time covered with large diftinct 

 dreams of the fluid, which run down its fides. 3. A 

 light yellow oil, called iweet oil of wine j and 4, a 

 fulphureous fpirit pafles over, the white colour and 

 fmell of which indicate the proper time for changing 

 the receiver, in order to have the ether feparate ; and 

 this is fucceeded by. black and foul vitriolic acid. 



Ether is a fluid of a peculiar nature. It is the 

 lighted and mofl volatile of all unelaftic fluids, and its 

 tendency to afiume the elallic form is fo ftrong, that 

 it is quickly diflipated in the ordinary heat of the at- 

 mofphere, unlefs confined. It is highly inflammable, 

 fo that it is dangerous to bring a candle near any con- 

 fiderable quantity of it, the vapour taking fire, and 

 Communicating the inflammation to the whole volume. 

 The acids with which fpirit of wine is diftilled, in order 

 to obtain ether, feem to effect this principally by rob- 

 bing the fpirit of part of its carbon, which latter fub- 

 ftance occafions the dark colour in the mixture, by 

 decompofing the acid. A fmall part of the acid ad- 

 heres to the ether in its afcent, and this conftitutes the 

 differences which exift among the ethers, according to 

 the. acid by which they were produced. 



The ACETOUS FERMENTATION is dill more fimple 

 than the fpirituous, and confifts merely in the abforp- 

 tion of the vital or oxygenous part of the atmofphere, 

 by which vinous fluids are converted into vinegar, 

 whence it appears that it is the proportion of oxygen 

 alone which conftitutes the vaft difference that exifts 

 between ardent fpirit and vinegar. That wine is con- 

 verted into vinegar, by the addition of oxygen, is 

 proved, as well from the general analogy of the for- 

 F 3 mation 



