i(«8 On ike Strengths of the Mixtures of Alcohol. 



IX. ' 



©B Areametry ; mere particularly as it relates to Alcohol of different Strengths and Tem- 

 peratures. By Cit. Hassenfsatz *. 



JL HE Author calls the inftruments made ufe of for determining the proportion of mix- 

 tures of alcohol and water, alcogrades ; and after a fliort preface refpeiling the ufes of fpi- 

 rituous and vinous fluids, he proceeds to enumerate the following fix methods of meafuring 

 the ftrength of brandies, &c. i. By the bubble or bead which appears when the fluid is 

 fhaken. 2. The fwimming or finking of oil poured therein. 3. Diflillation, to (how the 

 quantity of fpirit. 4. Burning the fluid in a filver veflTel, and noting the rcfidue. 5. Wet- 

 ting a known quantity of dry gunpowder with a little of the fpirit, andobferving the faci- 

 lity or difficulty with which it inflames. Thefe five methods are, as he remarks, not only 

 too uncertain to (hew the difl^erence of fpirit with the defired precifion, but will even give 

 very different refults, according to the management, with famples of the very fame fpirit. 

 6. The fixth method confifts in determining the fpecific gravity with the Areometer, which 

 as it has an appearance of precifion, deferves to be more minutely examined. 



The Areometer or inftruments for determining this fpecific gravity of fluids are of two 

 kinds, namely, i. a floating ball, with a ftem above, either graduated or fupporting a difli 

 to receive weights, and a counterpoife below to preferve the ere£l pofition ; and 2. a bottle 

 terminating in two fmall apertures, and capable of holding the fame invariable bulk o£ 

 fluid. 



The firft, namely, the hydrometer with the graduated ftem is moft in ufe. Inftruments 

 of this kind have been graduated in France by obferving certain points to which the fubfi- 

 dence was made in water and in alcohol, or in a faline folution. Nine of thofe more gene- 

 rally ufed in that country are exhibited in the following table : 



• AbftrafleJ from the fourth Memoir on this fubjeft, in the Annalet de Chimie, XXXIII. 



Taile 



