470 ART INDUSTRY AND RELATED OCCUPATIONS. 



Lyman^ agrees with me in considering it to be a product of the 

 transformation of the old volcanic rock, which is found close by in an 

 unchanged state as perlite breccia and trachyte. This is indicated 

 by its unstratified occurrence, its appearance, and the chemical 

 analysis. It is a compact rock, as hard as tiles, and having 2*5-27 

 specific gravity. Its colour is a greyish white or soft yellow, strik- 

 ingly resembling trachyte or felsite clay-stone, according to Giimbel.^ 

 The chemical analysis also agrees in this (see Appendix, table A). 

 The best kind is almost pure kaolin, while in other places the 

 rock is conglomerate, and intersected by numerous small quartz 

 veins, which, according to Mr. G. vom Rath's careful examination 

 at my request, are filled partly with very small quartz crystals, and 

 in other portions with crystals of iron pyrites, which under the 

 microscope appear distinctly in the form of dice and pyritohedrons. 



This porcelain stone is obtained in quarries, extending over a 

 range of about 1,000 meters. There are three principal kinds ; 

 one, white and entirely kaolinized, which also possesses the earthy 

 character of kaolin ; a second, blue and rich in quartz ; and a third, 

 yellow, and containing iron. The quarrying is entirely unsystem- 

 atic, the material being followed up as deeply and widely as may 

 be, without any great clearing away of other valueless materials. 



Eleven years ago, no one had any idea of the extensive character 

 of the deposit, nor of its depth. Any citizen, by making a small 

 payment to the town, can take away as much Arita-ishi as he needs, 

 but is not allowed to send any into other porcelain manufacturing 

 districts, nor to foreign countries. The water power of small streams 

 is used for stamping the material, and long before reaching Arita, 

 the preparations and arrangements for this work may be seen 

 along the roads leading to the town. 



The preparation of the paste is very much simplified, in com- 

 parison to that necessary in other porcelain factories, as the Arita 

 stone, in its several stages of decomposition, furnishes in itself the 

 materials for making it plastic and fusible. Mention has already 

 been made of the fact that the potter's wheel is not here as in other 

 places the simple form moved by the hand and rod, but much 

 oftener a combination of two wheels, the thick lower one being 

 turned with the foot. The axis of the wheel is not of steel, but a 

 hard -wood pointed tenon fastened to the floor. Some of the fac- 

 tories are very large for Japan, and manufacture, besides common 

 articles for domestic needs, a great many vases, some of them of 



duced by the action of solfataras upon soft, clayey sandstone." The latter, 

 however, appear in the immediate neighbourhood of the porcelain stone, with 

 the same proportion of argillaceous earth, and httle less silicic acid ; but show 

 no trace of a transformation into porcelain stone, or any other generic relation 

 with it. I agree with him, however, in regard to the action of the solfataras. 

 (See page 316). 



^ " Geological Survey of Japan. Reports of Progress." Tokio, 1879, p. 122. 



2 Dingl, Pol. Journal^ 227 Bd., p. 501. 



