484 



CONSIDERATION OF CARBON COMPOUNDS. 



gravity of 0.936 ; it is identical with the proof-spirit of the U. 8. 

 Custom-house and Internal Revenue service. 



Pure alcohol is a transparent, colorless, mobile, and volatile liquid, 

 of a characteristic rather agreeable odor, and a burning taste; it boils 

 at 78 C. (172 F.), has a specific gravity of 0.797, is of a neutral 

 reaction, becomes syrupy at 110 C. (166 F.), and solidifies at 

 130 C. ( 202 F.); it burns with a non-luminous flame; when 

 mixed with water a contraction of volume occurs, and heat is liber- 

 ated ; the attraction of alcohol for water is so great that strong 

 alcohol absorbs moisture from the air or abstracts it from membranes, 



FIG. 70. 



Liebig's condenser with distilling-flask. 



tissues, and other similar substances immersed in it; to this property 

 are due its coagulating action on albumin and its preservative action 

 on animal substances. The solvent powers of alcohol are very exten- 

 sive, both for inorganic and organic substances ; of the latter it readily 

 dissolves essential oils, resins, alkaloids, and many other bodies, for 

 which reason it is used in the manufacture of the numerous official 

 tinctures, extracts, and fluid extracts. 



Alcohol taken internally in a dilute form has intoxicating proper- 

 ties ; pure alcohol acts poisonously ; it lowers the temperature of the 

 body from 0.5 to 2 C. (0.9 to 3.6 F.), although the sensation of 

 warmth is experienced. Alcohol is not a food in the ordinary sense 

 of the word. Small quantities of diluted alcohol are oxidized jn the 



