Page:Brinkley - Japan - Volume 8.djvu/269

 the raw material of all seems to be the same kind of stone—no importance attaching to the fact that it is called clay sometimes—we must conclude that it depends upon the degree of heat whether the Kaga ware emerges from the oven a yellowish faience or stone-ware, or a white or bluish porcelain." Mr. Korschelt further observes: "The differences in the chemical composition of the Kaga wares are not greater, but rather less, than those in the wares of Arita, and both are manufactured from one raw material, a stone. But the analyses show that the porcelain stone of Kaga is not identical with the porcelain stone of Hizen. The former contains much less silica and much more clay-earth and alkalies than the latter." With regard, on the other hand, to the quantities of the constituents of Kaga wares, the following table will show that considerable differences exist:—

In preparing the glazing material, lixiviated ashes of Keyaki (Planecu Japonica) were mixed with the porcelain stones of Nabedani and Gokokuji. It is not to be assumed that all the materials entering into the above masses were known to the ancient potters of Kutani. Which of them they did know, and in what manner they employed them, there is unfortunately no hope of ascertaining now. A careful examination of Kutani specimens produced in the seventeenth and early part of the eighteenth century shows, however, four distinct varieties of ware. The first is stone-ware, heavy in proportion to its thickness, and of tolerably fine quality: its timbre poor, showing a large ratio of clayey substance; its colour grey, verging on brown, and its glaze impure white, often disfigured by minute pitting. The second is semi-porcelain, often no harder than faience, thin and light. The glaze of this variety, always soft and opaque and generally