_Inceptive Axes_: Vertical elements of cylinder.
_Points of Concentration_: In upper portion of vertical elements.
_Illustrations_: Figures 319, 320, 321, 327, 331, 332.
(_D_) _Zone of Enrichment_: full surface of exterior.
_Type of Design_: Free of formal conventionalized unit repeated on each vertical element. The units may be juxtaposed or may be connected by bands or similar links.
_Inceptive Axes_: Vertical elements of cylinder.
_Point of concentration_: In upper portion of vertical elements.
_Illustrations_: Figures 322, 323, 324, 326, 328, 329.
The reader should carefully consider the postulate and various divisions of Rule 7 and try to apply them to the material now under consideration. Acknowledgment is made for material supplied by the Rookwood Potteries for Figures 288, 289, 292, 293, 294, 297, 298, 315; 327 and 332; Newcomb Potteries, Figures 314, 316, 317, 318, 326; Teco Potteries, 329; Keramic Studio Publishing Company, 302, 307, 308, 310, 312.
Plate 51 illustrates the marginal surface enrichment of low cylindrical forms, with part surface enrichment of two higher forms.
For square or rectangular areas draw square rectangle, etc.
For shallow circular forms draw a circle.
For low cylindrical forms draw a rectangle; subdivide this if desired by a unit of measurement into two horizontal divisions.
For high cylindrical forms draw a rectangle; subdivide this if desired by a unit of measurement into two or three horizontal divisions. Rule 5e.
(_b_) Design simple contour enrichment based upon these units of measurement.
For square or rectangular areas draw diameters, diagonals, or both.
For shallow circular forms draw radii of the primary circle; concentric circles for bands.
For low cylindrical forms draw the elements of the underlying cylindrical form for extended borders or lines paralleling the top or bottom of the primary mass for bands.
For high cylindrical forms draw inceptive axes similar to low cylindrical forms.
(_e_) Locate points of concentration in these inceptive axes.
(_f_) Determine manner and amount of surface enrichment.
(_g_) Add leading lines and develop these into surface enrichment.
(_h_) Make potter's working drawing, full size (See Plate 26). Add the necessary amount for shrinkage and otherwise prepare the drawing for potter's use.