14 



su must have contained a considerable quantity of Mokuyki, an 

 impure form of urushi juice. 



Ishimatsu states that the part soluble in alcohol has the same 

 odor as the original, but never dries up as that does. It is brown- 

 ish-black, slightly sticky to the touch. With potassium hydrox- 

 ide it forms a bluish-black precipitate. The alcoholic solution 

 was precipitated by lead acetate. The precipitate was washed, 

 dried and analyzed, with the following results: 



MEAN 



C 49-84 51-06 50.45 



H 5.81 5.60 5.705 



O 40.-30 39-84 40.07 



PbO 3-50 4-05 3-775 



From which he calculated the formula C 20 H 30 O 2 . 



When he boiled the alcoholic residue with nitric acid it gave 

 off brown fumes and formed an orange colored mass, which when 

 washed was partly soluble in absolute alcohol. This alcoholic so- 

 lution formed a yellow precipitate with lead acetate or silver ni- 

 trate. The lead precipitate explodes when heated. It could not 

 be decomposed by sulphureted hydrogen without decomposition 

 of the acid, therefore he removed the lead by sulphuric acid, and 

 again precipitated with lead acetate, washed, dried the precipi- 

 tate, and estimated the lead as oxide, and the other constituents 

 by combustion. The results were as follows: 



MEAN 



C 26.77 27.10 26.93 



H 4.10 4.12 4.11 



NO 18.16 18.28 18.44 



PbO 47.41 47-43 47.42 



O 3.12 3.07 3-1 



From which he calculated the formula C 11 H 20 (NO 2 ) 2 PbOo 

 and for the original substance C^H^C^. 



The following is an abstract of Yoshida's investigation of 

 the alcohol soluble portion of the lac, which he calls Urushic acid. 



It is readily soluble in benzin, ether, carbon disulphide; less 

 easily soluble in fusel oil and petroleum of high boiling point ; in- 

 soluble in water; sp. gr. 0.9851 at 23. Remains unchanged at 

 1 60. Above 200 it decomposes slowly with carbonization. 

 From the alcoholic solution many salts can be produced, most of 

 which are slightly soluble in alcohol but insoluble in water. 



