33© 



M. TSUKAMOTO. 



large tubs when a certain kind of fermentation sets in, which 

 is recognizable by the development of gas. The Kaki-shibu 

 is prepared principally in the southern parts of Japan and 

 the best quality of it comes from Kyoto, Osaka and Nara. 

 The largest quantity of it comes from the vicinity of Hiro- 

 shima. The juice is generally prepared in August 1 and may 

 be applied fresh or after standing for two or three years. Some 

 persons claim that the juice is improved by long standing 

 in a cool place. In contact with the air an amorphous film is 

 formed on the surface, probably by oxidation, while on the 

 bottom of the vessels some bacteria and yeast-like cells are 

 deposited causing the characteristic smell of butyric acid. This 

 development of microbes proves that the preserving properties 

 of the Kaki-shibu do not consist in any peculiar antiseptic action, 

 and therefore the beneficial effects have to be traced to another 

 source. The Kaki-shibu leaves on evaporation a film insoluble in 

 water, and this substance fills up the pores of fibres and wood, 

 thus diminishing the water-holding capacity and the chances for 

 destructive fungi. It is further very evident that the fibres of 

 lines and papers are more closely united to each other so that 

 they closely cohere. Thus the deterioration by mechanical wear 

 and tear is considerably lessened. 2 One can easily convince 

 himself of this peculiarity by dipping filter paper in Kaki-shibu 

 and letting it dry. The difference in behaviour of this paper and 

 ordinary filter paper when rubbed in the moist state with the 

 fingers, is quite remarkable. The former offers considerable 

 resistance to the separation of fibres, while the latter does not. 



Chemical Examination. 



The most characteristic constituent seems to be a kind ot 



1 It is said by the practical Kaki-shibu-makers that the season for the preparation 

 of the juice is not of long duration, being only about 10 days ; both before and after that 

 season the quality and quantity of the product is inferior. 



2 The view expressed by Prof. I. Ishikawa (Journ. of Tokyo Chein. Soc. Vol. III. 

 (1882) Transactions p. 19.) on this same subject is a little different from that stated 

 here : namely, that the effective power of the juice is due to the formation of the film, 

 which is formed on the surface of the Shibu when allowed to stand for some length of 

 time. It seems to me, however, that the film formed on standing is different in its 

 nature from that formed on evaporation, and that the former can hardly be supposed to 

 be formed so soon. 



