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Hand-made Pottery

CHAPTER II
HAND-MADE POTTERY

Table of Contents

It is quite important that the potter should have a workshop—be it ever so small—which clay-dust and water will not harm. A light, dry cellar is a good place, or an outbuilding, if one lives in the country. The sense of freedom which comes from working in this way is a help in accomplishing good results. Protected by a long-sleeved apron and in such a place, one need not have a care for clothes or carpets. A stout old table, one or two chairs, and possibly a shelf, upon which to put the finished pottery—with these, and the potter’s wheel and bench (see Chapter III.), one will be well equipped. This is taking for granted that one has been able to buy one’s clay ready mixed. Otherwise there must be a tub for mixing the clay, and a sieve (see Chapter I.). In addition to the clay and the tools already mentioned in Chapter I., a pitcher of water will be needed, and a bowl for the “slip,” or clay thinned with water to the consistency of very thick cream. The potter is now ready for work.

Fig. 9

Small pieces of pottery, such as dishes and candlesticks, may be moulded with the hands from a single piece of clay (see Chapter VI.); but, for larger pieces, the strong and simple Indian process of building up with coils of clay is more satisfactory. This may be done in a variety of ways. Either the piece is formed by coiling the strips of clay within a mould, as described in Chapters VI. and VII., or by building it up by eye, assisted by a cardboard outline (see plate), or it may be formed entirely by eye, like the rose-bowl with a moth design in Chapter VI. The first method, while it is the simplest, is not the best to begin with, for one relies too much upon the mould, and unconsciously uses it too often, instead of training one’s eye to make a true and beautiful form. The second method—testing the form with a pasteboard outline as the piece is built—will be the best to start with. Having decided upon the shape he wishes to make, the potter draws it in outline (natural size) upon a piece of cardboard. It will be wise to choose a form as nearly like a cylinder as possible; for example, a jar for flowers. The outline sketch is divided by a vertical line ruled exactly through its centre. Another straight line, parallel with the first, is drawn three inches to the right of it. The outline is then cut out (see Fig. 9) so as to make a guide for the contour of the jar. A flat, round piece of clay, about five inches in diameter and half an inch thick, is now moulded and placed in the centre of a plaster tile. In the middle of this piece, a circle, two and three-quarters inches in diameter, is drawn with a tool. A lump of clay, which has been well worked to get out all air-holes, is rolled on the table with the palms of the hands (near the base of the thumb) lightly, yet with sufficient push to make the clay revolve wholly each time. If the roll flattens from too hard pressure, pat it into circular form, and continue to roll it until it is of even thickness—about an inch in diameter. It is then flattened evenly, one end is cut into a long point, and the coil is started on edge, narrow side up, on the circle drawn upon the clay bottom, which has previously had lines criss-crossed upon it back and forth with a steel tool, to insure the first coil’s clinging to it. To make this even more certain, a touch of slip is brushed lightly here and there over the edge of the circle. While the thumb and middle finger, on either side of the coil, support it, the forefinger presses it down firmly on to the bottom all the way around (see plate). It is so much easier to flare the walls of one’s piece than to make them straight, or bring them in, that they should be kept as nearly vertical as possible, especially in starting. When the circuit has been made, cut the end of the clay strip into a long, flat point which will fit evenly in with the one at the beginning of the coil, and press the edges together with the flat of the nail of finger or thumb. This is also done where the edges of the coil come against the bottom, outside and in. Quick, firm, yet short strokes of the nail up and down join the edges. In putting on the second row, no marking with the tool is necessary—only to brush it with slip. After the second row is added, the jar is put out in the air for half an hour or so, until it has stiffened a little. This is supposing that the potter is working at a time when the clay will not freeze. When the weather is cold, the piece must be left to stiffen indoors, as pottery that has once frozen is useless. The inside of the bottom and walls are then smoothed with great care, for, as it is to be a tall jar, this must be done before the walls get too high. Two more rows of coiling are now added as before, testing the shape by pressing the cardboard outline close against it all around the circumference. After this, the jar is again put out in the air for half an hour or so. This method is continued until the jar is built up.

BUILDING A PIECE OF POTTERY

1. Making the First Coil

2. Testing the Outline

3. Continuing the Piece

Should the walls become weak and insecure from working them too rapidly, let them dry for a longer time, several hours or over night, before finishing. Test the shape constantly with the cardboard outline. When the jar is as high as the drawing, or even a quarter to half an inch higher, let it dry over night. It should then be smoothed with an oval steel tool, which has a saw-toothed edge (see Fig. 5), to take the worst unevenness off. The tool is bent to fit the shape of the jar and held at right angles with it, smoothing it with short strokes in different directions. This is done inside and out. The hollows are also filled in. To do this, wet the spot first with slip and fill in with clay as nearly the consistency of that in the jar as possible. The sides are then made perfectly even with the oval tool with smooth edges, holding it as the saw-toothed tool was held. When there are no hollows or ridges and the walls are about a quarter of an inch thick, the surface of the jar is smoothed with a damp sponge and polished with the fingers and thumb inside and out, taking care in handling it not to hold it by the edge, but rest it in the hollowed hand. Should it have become very dry, as it will in a comparatively short time in warm weather, so that it is light-gray in colour, it will be wise to smooth it with sandpaper instead of with the sponge, as in this state even a little water may cause it to crack. One cannot learn too soon, or have too often impressed upon one’s mind, the risk of adding wet clay to a piece of pottery that is much drier. The natural shrinkage which has already taken place in the dry clay will be repeated in the wet, and, as it shrinks, it will crack the drier clay. Cracks in clay are of two kinds—those caused by shrinkage of the unbaked or green clay, and those that come from cooling too rapidly in the biscuit or baked clay. The former can usually be mended satisfactorily, but for the latter there is no remedy; the piece is spoiled.

To mend a crack in clay that is only partially dry, put a little slip into the crack and then work in, with a modelling tool, clay of the consistency of the piece. If, after drying longer, the piece cracks again—a long, deep crack, that goes through to the inside—there is no way to mend it except by cutting the clay out on either side for quite a space beyond the crack, brushing both sides with slip, and filling in with clay as nearly as possible the consistency of the piece. This is pressed in in small bits, little by little, until the gap is filled. If it should crack again in small, short places, fill them with dry, powdered clay, pressed in and moulded with a steel tool.

In case of the piece cracking when it is bone dry—that is, after it has dried for several days and is pale-gray in colour—grind some pieces of baked clay to a fine powder, add enough water to make a soft, yellow paste, and fill the cracks with it.

The edge of the jar is cut as even as possible with a tool, and then made perfectly true by the following method: A little water is poured on a ground-glass slab, and the jar, held bottom up, is moved firmly but rapidly round and round on the wet surface, and then quickly taken up (by sliding it off at the edge of the slab) before it clings to the glass. The bottom must now be finished. The jar is first placed bottom up on a slab or table, then a circle is drawn with a pencil at about half an inch from the edge of the bottom. This is outlined with the pointed steel tool, and the bottom within the circle is evenly and carefully cut out with strokes of the oval, smooth-edged tool, so that the outside ring shall form a ridge not over one-sixteenth of an inch above the depressed interior of the circle. The potter now cuts his initial or mark, which is made in as simple lines as possible, into the bottom with firm, deep strokes. If the jar is not very dry, a wooden modelling tool may be used for this. Otherwise, the pointed steel tool is chosen. Care should be taken not to cut under the edge in making these incised lines. The edges should instead be bevelled, so that, when the glaze is put on, it will flow more freely over them.

If possible, this jar, being large, should be fired in the biscuit—that is, before it is glazed, and then again after it has been glazed; unless one is obliged to send it a long distance to be fired, so that more than one firing is impracticable, in which case it must, of course, be glazed on the unbaked clay.

A pale green glaze (see directions in Chapter V.) will complete it.

In packing to send pieces to a far-off kiln by express, use a wooden box, and, after lining it with newspaper, wrap the pieces in soft paper, and pack them carefully in sawdust.