Another example of the value of variety is to be found in the curve of the profile. A line that is simple but constantly changing in its degree of curvature—as, for example, an elliptical curve—is more pleasing than an arc of a circle, which is sometimes called the curve of limitation. It should be noted that a curved form, in order to be forceful, should have some dominant curve in combination with others which are subordinate. The profiles illustrated in the following drawings have this dominant element and are in no case composed of arcs of circles. These varied, interesting, yet simple lines—live lines as they are sometimes called—consisting in each case of only two or three elements, are given here merely as suggestive material. A little experimenting will show unsuspected possibilities in strong, forceful curves, and the young student is advised to make many experiments in the effort to discover such possibilities. An example of profiles to be avoided is given in Problem II, on [page 309]. That these are vase forms and not bowl contours is immaterial. A is commonplace because the two parts of the curve are too much alike. B is unrestful in its three curves of nearly equal size. If the suggestive profiles illustrated in the foregoing drawing be turned upside down it will be noted that very few of them seem as pleasing as before. It will be found also that a different ratio of height to diameter will give very different effects with the same profile. A bowl having top and bottom alike may, so far as design is concerned, be classed with the pill box. We don't know which is the top until we have spilled the pills. If attractive pieces of pottery are found with the top and bottom of equal diameter and with curves in themselves objectionable, it will invariably be found that the attractiveness consists in some beauty of glaze, colour, or decoration which is prominent enough to conceal the defects of form.
Natural Forms.—It may be well to add a word here in regard to the imitation of natural forms in designing the general shape of any piece of pottery; and that word is a very brief one. Avoid them. Nature is a great teacher in all branches of art; but in pottery her suggestions are to be used as decorative elements rather than for fundamental shapes. A fish with a flower in its mouth does not seem appropriate; but a bowl for water-lilies, while it may not take the form of a fish, might reasonably have a fish as an element of its decoration.
Testing Profiles.—A good way to study the effect of the profile of both sides of the bowl is to fold the paper on which the profile is drawn vertically through the centre and transfer the line reversed by rubbing the back of the paper, thus giving the other half of the drawing in exact symmetry. When the general shape of the profile has been tested in this way one side should be redrawn carefully; then, with the paper folded along the centre line, so that the pencil line falls outside, the whole form may be cut out; and then it may be unfolded. The next step is to begin to build up the design in clay.
The Building.—Roll out a coil of clay a little thicker than the bottom of the bowl is to be; perhaps 3⁄8 or 1⁄2 of an inch will serve, since the bottom is to be hollowed slightly by scraping. The roll should be uniform in diameter and rolled as little as possible, in order that it may not become too dry. Upon the piece of paper or the plaster bat start to coil the roll from the centre until the desired size is reached, then smear the rolls together, working toward the centre. Turn the coil over and work the other side together, truing up the circle and making the bottom of uniform thickness. Avoid the use of water in smoothing the coils together. It may seem to make the work easier, but it softens the clay and invites careless work.
Manipulating the coil
With another coil begin to build up the sides, making a complete circle, and, having pinched off the ends where they meet, join them carefully. Lay two or three coils in this fashion, pressing each coil firmly into place as it is laid, and smooth them together as in the base. The process is illustrated in the drawing. If the clay is very soft, the work may be set aside to harden a little, while a beginning is made upon other pieces. It is well to have two or three pieces in the process of construction at the same time.
Testing the Work.—A template or gauge will be needed to test the work as it progresses from the first rough stages to the finish. This is made of card-board by cutting out an exact copy of the profile, leaving at the bottom sufficient width to insure rigidity when the template is held upright on the table or bat.
