334 



M. TSUKAMOTO. 



violet black by ferric chloride ; in cold alcohol dissolved easily 

 with a fine red color; in caustic soda, with a brown red color. 

 The aqueous solution is precipitated on a moderate addition of 

 sulphuric acid. From genuine oak-red, however, our substance 

 is distinguished by its solubility in cold water and cold alcohol. 



The liquid from which the red precipitate was separated 

 was of a dark reddish brown color, and contained evidently 

 more of the red substance in solution, The sulphuric acid was 

 at first removed by barium carbonate and then the rest of the 

 tannin by basic lead acetate. The filtrate now obtained was 

 treated with sulphuric acid to remove the lead, and the filtrate 

 evaporated on the water bath witli the addition of barium 

 carbonate. The search for sugar or chitosamine was in vain. 

 I intend to repeat this experiment with the insoluble film obtain- 

 ed by evaporation of Kaki-shibu. 



Finally for analytical results we 



have : — 





New Kaki-shibu. 



Old Kaki-shibu. 



Specific gravity at I5°c 



1.0230 



I.O250 



Total solid Matter. 



6-39'X 



5-874% 



Total fixed organic Matter. 



5-993 „ 



5.566,, 



Ash. 



0.398 „ 



O.308 ,, 



Insoluble film. 



3-420 „ 



3-512 ,, 



„ . (as gallotannic acid, 

 linn in ^ • • • 

 ( as quercitannic acid. 



4773 ... 



3 449 



4-9 2 7 » 



3-560,, 



Volatile acid (as acetic acid.) 



0.087 „ 



0.217 ,, 



Fixed acid (as lactic acid.) 



0.085 



0.102 ,. 



Nitrogen J 





0.030 , , 



General Conclusion. 



The industrial value of Kaki-shibu is due to its containing 

 a peculiar tannin which in some respects differs from all other 

 kinds of tannin known, since it is insoluble in alcohol and water, 

 and soluble in dilute acids. This tannin becomes insoluble 

 when the volatile acid of the Kaki-shibu evaporates, and the 

 insoluble film thus formed protects fibrous objects against 

 mechanical wear and tear. A partial oxidation in contact with 



1 This nitrogen is probably due to an admixture of small quantities of protein. The 

 amount varies greatly. 



