SPECIAL SUBJECTS
understood that when the base is of wood, the enamel design, separately manufactured, is inserted, when complete, in the wood. The melting process reduces the volume of the enamel paste, so that, when the vessel emerges from the oven after the firing, the spaces within the cloisons are found to be only partially filled. An additional quantity of paste has to be inserted, and once more the object is placed in the oven. This process has sometimes to be repeated several times before the cloisonned spaces are sufficiently full. Moreover, since all the pastes do not fuse at the same temperature, there is here another reason for independent firings, and risks are thus introduced which sometimes prove fatal after an object has been almost completed. Finally, the vitrified pastes having completely filled the cloisonned spaces, the whole surface is ground and polished with great care until it becomes perfectly even and shows a soft lustre. Thus finished, the enamel is known in Japan as kazari-jippō (ornamental enamel). The grinding and polishing process is often dispensed with, especially when translucid pastes are employed. Enamel decoration of the latter class is called nagashi-jippō (poured enamel).
The term shippō (jippō in composition) literally signifies "seven precious things." It was used originally to designate gold, silver, and various jewels about the names of which there is some uncertainty. In China the use of jewels to decorate vessels of gold, silver, or bronze was practised at a remote epoch, and to such objects the designation shippō was applied. There can be little doubt that verifiable pastes were soon employed as a substitute for jewels in this kind of decoration, and that champlevé enamelling thus
329
