The physical equilibrium which exists in the balanced “seesaw” of our childhood and the optical balance which is the result of the proper adjustment of masses within the confining edges of a design are similar, in that each is an equalizing of forces of attraction. In the former the force is gravity; in the latter, the attraction to the eye, which varies with the size and tone of the mass. While the force of gravity usually brings balancing masses to a horizontal alignment, optical balance may bring the masses in a design into equilibrium on any desired line, horizontal, vertical, or diagonal.
The attraction which a mass possesses varies directly with its size and tone. Thus a mass of four square inches, solid black, will be twice as strong in attraction value as a mass of two square inches, solid black. It will also be twice as strong in attraction value as a mass of four square inches, neutral gray (the gray being half the value of black). The attraction value of gray tones particularly affects the consideration of blocks of type which vary in depth of tone according to the blackness of the type face, closeness of spacing, etc. Since the “seesaw” must have its sawhorse and the weighing scale its point of support, it follows that any condition of equilibrium, physical or optical, demands a point of balance. In design, this point will determine the location of the related masses.
It will be apparent upon further thought that the point of balance should have some relationship to the edge or confines of the design. The confining edge of the design is usually a rectangle, on the printed page. The location of a point of balance within this rectangle tends to divide it. How shall it be divided in the most interesting way? By applying the ratio of good proportion. So the point of balance may be located usually on a line which divides the page into parts of 2 and 3. When equal masses are to be balanced it is obvious that they will be equidistant from the point of balance. When the masses are unequal the point is at unequal distances from the centers of the masses.
These unequal distances have the same ratio as the masses themselves, but the larger mass is always the shorter distance from the point. If 1 pound is to balance 4 pounds it is obvious that the 1-pound mass must be 4 times as far from the point of balance as the 4-pound mass. Hence, to balance two masses in a rectangle, the point of balance will be found by proportion, placing it on a line which divides the rectangle into parts of 2 to 3. The balancing of the masses across this point will then be a matter of determining their relative distances from it. It is apparent that the larger of two masses may be far enough from the point of balance so that it will force the smaller entirely out of the rectangle. It is of course easy to move the larger closer to the point which automatically brings in the smaller. What constitutes a proper distance from the edge of the rectangle will be discussed under “Margins,” in the book on Typographical Design.
The balance of three or more masses within a rectangle involves the consideration of two at a time, balancing the pair or pairs with the remaining mass or masses. Balancing 3 with 1 gives the balancing point P. Taking 3 plus 1 from the point P, we locate the mass 2 to balance them across the line AB which divides the rectangle in good proportion. The point p then becomes the balancing point for the entire group. Mathematically, 3 plus 1 equal 4; 4 is twice 2; therefore the mass 2 must be twice as far from the point p as the balanced masses 3 plus 1. Two other combinations might have been worked out with the masses in plus 2, balanced by 1, the mass 1 being placed five times as far from the point p as would the point P. Or 2 plus 1 might have been balanced by 3, in which case the distances would have been equal. The application of these principles of balance to the problems of typography is largely a matter of influence. The typographer should be guided by them but he need not make mathematical calculations if his eyes be trained to judge relative attraction values so that he can arrange his various masses to secure balance.
