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common crockery-ware, formed of the purer and whiter clays, in which iron exists only in small quantities. Porcelain, which is the most beautiful and costly of all, is made only of argillaceous, that is, clayey minerals of extreme delicacy, united with silicious, or flinty, earths, capable of communicating to them a half-transparency when subjected to great heat.
Scarcely any other machine used in the arts has lived so long, and undergone so little change, as the potter's wheel. Egyptian monuments, and on other records of antiquity, there are representations of it similar, in all the essential particulars, to that of our own day. Indeed, nothing can be more simple than its construction. The potter sits on a kind of stool or bench, behind a small whirlingtable. His knees are placed, one on each side of the central support of the machine, so as to give him a command over it. This whirling-table, which is simply a circular piece of wood, whose breadth is sufficient to carry the widest vessel that is to be made, is fixed on the top of an upright stem or shaft, so that if the shaft be made to rotate, the piece of wood or
table must rotate also. The whole apparatus is rather below the height of a common table. The material which is to be formed into a vessel is put upon the circular board, and there remains till fashioned; the board and shaft being made to revolve horizontally, while the potter with his hands gives the required form to the turning clay before him.
Those who witness this process for the first time, seldom fail to be astonished. Nothing can be more complete than the mastery which the artificer has over the work he has in hand: he seems as if he could do anything, everything with it. At one moment the lump of clay is a shapeless mass; at another a circular cake; then a ball; then a pillar or cylinder, hollow or solid; then a jug; then a basin; next, a sudden movement converts it into a bottle, or a plate, or a saucer. His hands work and form the yielding figure with a rapidity almost inconceivable; and the visitor wonders where the clay comes from, and whither it goes, as one form is being rapidly exchanged for another. It is true that when at his regular work the potter does not give all these various shapes to one
piece of clay; but a stranger has frequently afforded to him an opportunity of seeing that the workman can do so.
Every potter, or thrower," as he is sometimes called, is attended by two assistants, who are named respectively the "ball-maker" and the "wheelturner." The former has near him, or her, a quantity of prepared material, having precisely the quality and consistence, or firmness, required for the potter's operations. The ballmaker separates the clay into proper portions, each suited to the manufacture of one particular kind of vessel, and works it up into a rude ball convenient for handling by the thrower. The services of the wheel-turner depend on the manner in which the circular piece of wood, or table, is made to rotate. In the early stage of the porcelain manufacture in England, the board was put in motion by a wheel provided with spokes, which the thrower moved with his foot; the labour, however, was so great, that this method was not adapted to the production of large articles.
Another plan used in past times was, to have a crank in the middle of the shaft, with a long rod working upon it,
motion being given to the apparatus by the rod being pushed backward and forward. The customary mode at the present day is, to have a rope passing from the upright shaft to a large wheel at a distance, which wheel is turned by a boy under the direction of the potter.
With this very simple kind of lathe, and with a few tools equally simple, does the workman proceed to fashion all those articles of porcelain which are round in their form, whether cups, basins, or vessels of any other sort. When the shape is not quite circular, other methods of working are employed.
Let us suppose, as an example, that a basin, such as we usually put sugar in on our tea-tables, is to be made. The man places a proper quantity of clay upon the whirling-table, striking it down rather forcibly, in order to make it hold firmly to the wood during the process of formation. He then gives directions to the wheel-turner to set the machine in motion; and with his hands, which he wets in a pitcher of water near him, he presses the revolving clay, bringing it into a cylindrical shape. This cylinder he forces down again into a lump, and continues these operations
-squeezing the material into various forms-until he has driven out from it every airbubble it contains, a precaution of very great importance. Then putting his two thumbs on the top of the mass, he slightly indents, or hollows it, as а first indication of the inside of the intended basin, jug, or jar, or whatever thing of the kind he is making. He now proceeds, with a dexterity that seems almost marvellous, to give both the inward and outward curved form to the vessel. With his thumbs inside and his fingers outside, he so draws, and presses, and moulds the clay, as to give to the one side a convexity, or bulging outwards, to the other a concavity, or hollowness inwards; and he imparts to the whole substance a proper evenness, without breaking the material, or disturbing its circular form.
While the thrower's hands are upon the clay, a very slight alteration in the amount or direction of the force he uses would change a basin into a saucer, or into some other object whose curves are very different from those of a basin. The oddness of these transformations might often make a spectator smile, were not his admiration excited
by the readiness and skill of the workman who produces them. According to the shape and size of the object which he wishes to make, the thrower requires the wheel to move with various degrees of velocity, in which he instructs his wheelturner.
The general figure of the articles, inside and outside, is obtained, as I have just said, by the thumbs, fingers, and palms of the hands. But as this could not insure perfect accuracy, the workman is provided with small pieces of wood called "profiles," or "ribs,' each of which is shaped in accordance with either the exterior or interior of some particular kind and form of utensil.
Holding one of these “ribs' in his hand, and applying it to the surface of the article, the thrower scrapes off the superfluous portion at any projecting or mis-shapen part, and thus makes the whole circumference conform to the shape of the "rib." The fragments thus removed, called by the workpeople "slurry," are thrown aside among the unused clay. If a number of pots, mugs, or pitchers are to be exactly the same size, the potter sometimes fixes pegs in the stand on which
the work is placed, which serve as a guide to him in regulating the distance to which the clay is to be pressed out, and beyond which it must not reach. When the vessel, by the aid of the hands and the small workingtools, is complete, it is cut from the supporting piece of clay, or from the board, by means of a piece of brass wire, and placed on a shelf to dry.
In this manner an endless variety of earthenware is formed, including all those utensils which have, both outwardly and inwardly, a uniform roundness. And not only are such articles thus produced, but portions of clay are similarly brought into a cylindrical, or pillar-like, form, as the material from which useful or ornamental objects may afterwards be fashioned at the turning-lathe. Candlesticks, taper-stands, fancy
baskets, door-handles, and a host of other things are now thus manufactured.
The operation of turning these productions is carried on very much in the same manner as the turning of wood. They are allowed to remain until, by the evaporation of moisture from the damp clay, they have acquired a degree of dryness which is known among the workmen as the "green state." In this condition the shaping and smoothing of the surface are better effected than when the material is either damper or drier. As a turner in wood can cut out a uniform cavitysuch as is required in a candlestick-just as well as a circular exterior, so can the porcelain or earthenware-turner; and it is in this way that many articles of common use are finally brought into their proper form.