Rule 2b. If the primary mass is divided into three horizontal divisions or sections, the dominance should be placed in the center section with varying widths in the upper and lower thirds.
Sequential Progression of Minor Horizontal Space Divisions
Rule 2c. A primary mass may be divided into three or more smaller horizontal masses or sections by placing the larger mass or masses at the bottom and by sequentially reducing the height measure of each mass toward the smaller division or divisions to be located at the top of the mass.
Vertical Space Divisions
Rule 3a. If the primary mass is divided into two vertical divisions, the divisions should be equal in area and similar in form.
Rule 3b. If the primary mass is divided into three vertical divisions, the center division should be the larger, with the remaining divisions of equal size.
Rule 3c. In elementary problems, if more than three vertical divisions are required, they should be so grouped as to analyze into Rules 3a, and 3b, or be exactly similar.
Appendages
Rule 4a. The appendage should be designed in unity with, and proportionately related to, the vertical or horizontal character of the primary mass, but subordinated to it.
Rule 4b. The appendage should have the appearance of flowing smoothly and, if possible, tangentially from the primary mass.