of fractional precipitation. Farther preliminary experi- 

 ments showed that 50^ alcohol extracted from the original 

 material all of the substajice or substances which gave the 

 light colored precipitate and dissolved only a small amount 

 of the tar. 



288 gm. of the crude material were then extracted several 

 times with 50^ alcohol and filtered; the insoluble tar was 

 washed and saved for examination. To the filtrate was added 

 an excess of a solution of lead acetate in 50/S alcohol. The 

 large precipitate, which will be designated as "precipitate 

 A", was filtered and drained by suction in a Buchner funnel. 

 The alcoholic "filtrate A" was saved. Precipitate A was 

 extracted with ether in Soxhlet extractors until the ether 

 came over practically colorless, the operation being inter- 

 rupted from time to time to stir up the precipitate in the 

 thimble. The green colored ether solution was saved for 

 future examination. The lead precipitate, after extraction 

 with ether and drying ^weighed about 116 grams. A pOrtilfton 

 of this lead compound was decomposed by hydrogen sulphide in 

 a mixture of water an. ether which was well shaken during the 

 operation. The ether was separated, filtered, and evaporated 

 under diminished pressure without heat ^ and there rer.ained a 

 yellow oily looking residue having a plea^jant odor. When the 

 ether and water were completely removed in a vacuum desiccator 

 a hard, brittle, yellow resin weighing about 16 grams was 



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