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SEPTEMIBER 3, 1880.] THE PHOTOGRAPHIC NEWS. 429 of silver, as far as the eye can reach, is the Bristol Channel, sixty miles away. Then turning northwards, the eye ranges over a vast plain, the valley of the Severn, rich in fat meadows and luxuriant cornfields, bounded by the hills dominating the vale of the White Horse. Eastward, Malvern itself nestles at the foot of the grand Worcester shire Beacon, and over that shines the tower of Worcester Cathedral, standing up distinct and clear amidst the group of houses and factories which cluster round it. So let us clamber to the roof of the well-appointed four- horse coach, and by the lovliest highways and byeways we, in an hour and a-half, clatter up Foregate Street to the Cross, and are in the midst of the quaint old city, with its old-fashioned houses, picturesque roofs, and narrow streets. Worcester is the seat of the celebrated Royal Porcelain Works, which for the last 150 years have turned out some of the most delicate and artistic of English work in porce lain ; it is called “ Royal ’’ because George the Third, visit ing the works in 1788, granted his warrant permitting the establishment to be so designated, and well deserves its name, not only on account of the superb works of art produced in the ateliers, but also for the right royal hospi tality with which it receives visitors, and permits them to view the interesting series of operations involved in the production of the higher branches of ceramic art. In an article upon ceramic photography it might scarcely be thought necessary to touch upon the manufacture of the porcelain itself; and so long as photography is con tent to produce pictures upon enamels specially made, and of comparatively small size, it would seem to be quite superfluous; but when it becomes a question of employing photography as a decorative art, and to apply it to porce lain, it is absolutely necessary that the operator should have some knowledge of the substance he is working with, the manner in which it is glazed, and the colours he pro poses to employ to this end. Therefore the reader will be introduced to the various stages of porcelain manufacture with a view to arriving at a competent knowledge of the subject in an enlarged and commercial sense. The materials of which Worcester porcelain is com posed are not found in the locality in which the manu factory is situated, so that the trade cannot be said to be indigenous. Doubtless, in former years, considerable difficulty was experienced in obtaining the necessary materials; and it was not until Brindley opened out the district by his system of canal navigation, and later on, George Stephenson, with his iron road, made facilities for transit unknown before, that the Worcester porcelain became important commercially as well as artistically. The visitor who joins a party of four or five, in the waiting room, having the same object in view as himself, is conducted, first of all, to the room in which the materials are ground. The mills are vast tubs, paved with a very hard stone called chert; in the middle revolves a vertical shaft, attached to which are four strong arms, carrying circular stones which, when the machinery is in motion, travel round the inside of the tub, and thoroughly crush up and disintegrate the material placed therein. The principal ingredients of porcelain are china clay or kaolin, petuntse (which is a decomposed granite rock found in Cornwall) felspar from Sweden, and calcined bones. The use of the latter article makes the chief difference between English and Continental porcelain, the former being known as soft, the latter as hard, porcelain. These ingredients having been placed in the tubs with a suffi cient quantity of water, the machinery is put in motion, the ponderous stones begin to revolve, and the grinding goes steadily on, sometimes for days, until the whole is ground into a greyish looking soup. The materials having been thus separately ground, now pass into what is called the slip house, and the various ingredients comprising the porcelain are here mixed together, being stirred up by machinery having radiating arms fixed on a vertical shaft. These arms are provided with powerful magnets, and as they move through the fluid the particles of iron which may have been present in the raw material, or may be the result of abrasion of the machinery, are attracted by these magnets, and arc thus prevented from sullying the delicate print of the porcelain by their presence. The material, which is designated sltp, now passes through a series of sieves of exceedingly fine silk lawn, which allow nothing but the perfectly ground mixture to pass, keeping back all the coarser particles. The next process is to get rid of the surplus water, to which end the slip is pumped into what is called the clay press, a ma chine with a number of chambers lined with linen bags; the slip is subjected to hydraulic pressure, until sufficient of the water is squeezed away to cause it to assume the consistency of dough. The dough is next taken to a vault called the clay cellar, and is there subjected to a most complete kneading, with a view to giving it consistency and toughness ; this is the material used in the actual manufacture of porcelain ; to the eye it is a greyish-looking mass, the particles composing it being of exceeding fineness; to the touch it gives the idea of great toughness and tenacity. The ancient method of making circular vessels was by means of the potter’s wheel, perhaps the most ancient mechanical contrivance of which any record has been pre served. At the Worcester Porcelain Works this mode of making cups and basins is shown greatly to the gratifica tion of visitors, although the process is not used for busi ness purposes. It is very interesting to see the potter take the lump of clay, which has been previously' carefully weighed by his assistant, throw it on his wheel, which revolves horizontally, then with deft and practised fingers, fashion and mould it, and presently there comes up, under his skilful hands, the most delicate and elegant form in the plastic material; to this he affixes a handle, which has been pressed in a mould, merely using a little of the fluid slip, which forms a most powerful junction between the two. Most of the articles manufactured in porcelain are made in moulds, and the visitor notes with some surprise the large size of the familiar objects; this is to allow for the shrinkingin the firing; the pressed and moulded articles are stored in a drying-room, preparatory to being placed in the gigantic kiln, where they will bo exposed for hours to an enormous heat. The kiln has the appearance of a circular room dome shaped, the centre going up into a sort of wide chimney ; this is about fourteen feet in diameter, and has six or eight furnaces arranged at intervals round it. It is built with fire brick, and encircled with strong iron bands. The entrance is by a doorway, and the articles to be fired are placed in the kiln in what are . called seggars, which are cases made of fire clay, and of shapes suitable for the various articles to be placed in them. Each large piece has its own particular seggars, in which it is carefully placed, imbedded in calcined flint. The smaller articles are placed several together, but always imbedded in the pow dered flint, and properly supported to prevent them getting out of shape. The seggars being filled with the ware are now placed in the kiln, piled one above another in the most careful manner; the proper placing and filling up of a kiln, con taining, perhaps, many thousand pieces of valuable ware, being a work requiring great skill and experience. As soon as the kiln is full, the doorway is bricked up, the great furnaces are lighted, and for forty hours are kept going. The kiln becomes heated, then red-hot, then at a white heat; when the whole interior seems to be a mass of incandescent fusion. On looking through one of the small trial holes, the eye sees nothing but a blinding white heat, which strikes through the hole through which you have been peering, with most unmistakable power. This terrific heat is kept up for some forty hours or so ; then the kiln । takes forty-eight hours to cool. The doorway is broken