86 Cbemifiry. 



black animal oil of Dlppol, were obtained in three hovjrs. 

 The receiver was clofeiy luted to the worm, and the air in 

 it was perfectly traiifparcnt. Upon taking away a part of 

 the lute, in fuch a manner as to permit the air of the atmo- 

 fphere to enter the receiver, it became immediately filled with 

 a thick brown yellow cloud of fmoke. 



Having made a variety of comparative experiments, to de- 

 termine the difi'ennce in the quantity of the prodnft, by dif- 

 tillino-with and without the lute, it was found that five times 

 as nuich of the volatile alkaline fpirit could be obtained by 

 carrying on the diltillalion without the lute, as could be pro- 

 cured, in the fame fpace of time, with the application of the 

 lute. 



Lavoifier fuppofes, that when ammoniac is obtained from 

 animal fubftances, the hydrogen and the azot of thefe bodies 

 unite together, and form the volatile alkali ; but it appears^ 

 from what has been faid, that the azotic air of the atmo- 

 fphere enters into the worm of the refrigeratory, joins the 

 hydrogen of the bones, and fo forms the ammoniac. 



Manufacturers of the volatile fpirit of fal ammoniac may 

 take fome valuable hints from thefe experiments. 



3 . Of Putrid Urhie exprj'ed to the Fro ft. 



A quart of the mofl putrid urine, and of as yellow a co- 

 lour as gamboge, was expofed two nights to intenfe cold, 

 when it became perfeclly fweet, and was as colourkfs as 

 rock water. 



May not this wonderful change be attributed to the agency 

 of the oxvgen gas of the cold atmofpheric air? 



The acid of citrons not only neutralifes the volatile alkali 

 of putrid fubilances, but completely deftroys the naufeous 

 fmell which exifts independent of the ammoniac. The ful- 

 phuric and muriatic acids have no fuch effeiil. Docs the 

 oxvgen of the citric acid aft here likewife ? Lowitz, a Ruf- 

 fian chemift, fuppofes that charcoal neutralifes the putrid ef- 

 fluvia of animal bodies; but, in my opinion, it a6ls mi'cha- 

 nically, in preventing the putrid particles of matter from 

 flyiug into the lir. 



4. Of 



