FIX LIQUIDA 41 



inol, from styrax; gurjuresinol, from gurjun balsam; and guaiac- 

 resinol, from guaiac resin. 



(3) Resinotannol Resins are aromatic derivatives that behave 

 towards iron salts and some other reagents like tannin and yield 

 picric acid on oxidation with nitric acid. The following have been 

 isolated: Aloeresinotannol, from aloes; ammoresinotannol and 

 galbaresinotannol, from ammoniac; peruresinotannol, from balsam 

 of Peru; siaresinotannol and sinnaresinotannol, from benzoin; 

 and toluresinotannol, from balsam of Tolu. 



(4) Resene Resins form a group of resins which appear to be 

 associated with bitter principles. They are insoluble in alkalies 

 and with difficulty acted upon by reagents. They include alban and 

 fluavil, from gutta percha; copalresene, from copal; dammaresene, 

 from dammar; dracoresene, from dragon's blood; olibanoresene, 

 from olibanum. 



(5) Glucoresins or glucosidal resins, as the resins of jalap and 

 scammony. 



Resins occur in 33 families of the Spermophytes. 



Fix LIQUIDA. Tar. A product obtained by the destructive 

 distillation of the wood of Pinus palustris and other species of Pinus 

 (Fam. Pinacese), evergreen trees indigenous to the southern United 

 States, particularly near the Atlantic Coast and the Gulf of Mexico. 

 Tar is obtained by distillation of the wood without access of air, the 

 tarry liquid being separated from the aqueous mixture consisting of 

 wood naphtha and pyroligneous (crude acetic) acid. The amount of 

 tar obtained in the operation varies, depending on how rapidly the 

 wood has been heated. If the wood is heated slowly the yield is 

 about 5 per cent, if rapidly heated it is increased to nearly 10 per cent. 



Description. Semi-fluid, viscid, blackish-brown, non-crystalline, 

 transparent in thin layers, becoming granular or crystalline (due to 

 the separation of pyrocatechin) and opaque with age; odor peculiar, 

 aromatic, taste pungent. Tar is soluble in alcohol, fixed or volatile 

 oils, and solutions of potassium or sodium hydrate ; it is heavier than 

 water and slightly soluble in it; the solution is of a pale yellowish- 

 brown color, has an acid reaction, yields with a dilute solution of 

 ferric chloride, a reddish color, and with a stronger solution, an olive- 

 green color, due to the presence of pyrocatechin (distinguishing it 

 from Juniper Tar), and is colored brownish-red by an equal volume 

 of calcium hydrate test-solution. The petroleum ether extract is 

 colored greenish by a 0.1 per cent solution of copper acetate. 



Constituents. Tar consists of a resinous substance, with which 

 are admixed a small quantity of turpentine, acetic acid, methyl 



