_Ka-o-lin_ is the name given by the Chinese to their porcelain clay, and _pe-tun-tse_ to the other ingredient in their China ware. Specimens of both these have been brought into England, and found to agree in quality with some of our own materials. Kaolin is the very same with the clay called in Cornwall [Transcriber's note: word missing] and the petuntse is a granite similar to the Cornish moorstone. There are differences, both in the Chinese petuntses, and the English moorstones; all of them contain micaceous and quartzy particles, in greater or less quantity, along with feltspat, which last is the essential ingredient for the porcelain manufactory. The only injurious material commonly found in them is iron, which discolours the ware in proportion to its quantity, and which our moorstones are perhaps more frequently tainted with than the Chinese. Very fine porcelain has been made from English materials but the nature of the manufacture renders the process precarious and the profit hazardous; for the semivitrification, which constitutes porcelain, is necessarily accompanied with a degree of softness, or semifusion, so that the vessels are liable to have their forms altered in the kiln, or to run together with any accidental augmentations of the fire. NOTE XXII.--PORTLAND VASE. _Or bid Mortality rejoice or mourn O'er the fine forms of Portland's mystic urn._ CANTO II. l. 319. The celebrated funereal vase, long in possession of the Barberini family, and lately purchased by the Duke of Portland for a thousand guineas, is about ten inches high and six in diameter in the broadest part. The figures are of most exquisite workmanship in bas relief of white opake glass, raised on a ground of deep blue glass, which appears black except when held against the light. Mr. Wedgwood is of opinion from many circumstances that the figures have been made by cutting away the external crust of white opake glass, in the manner the finest cameo's have been produced, and that it must thence have been the labour of a great many years. Some antiquarians have placed the time of its production many centuries before the christian aera; as sculpture was said to have been declining in respect to its excellence in the time of Alexander the Great. See an account of the Barberini or Portland vase by M. D'Hancarville, and by Mr. Wedgwood. Many opinions and conjectures have been published concerning the figures on this celebrated vase. Having carefully examined one of Mr. Wedgwood's beautiful copies of this wonderful production of art, I shall add one more conjecture to the number.