Type sizes for lettering books generally range from 6 point (very small) to 36 point (relatively large), depending on several factors, including the size of the book and the relative degree of legibility desired. Design of the type face and proper arrangement of the lettering, however, are as important for legibility as is the size of the type. As a general rule, the factors governing lettering are: 1) only one type face should be used on an individual book or set of books: 2) spacing between lines should be logical and pleasing to the eye; 3) spacing between letters should be the same on all lines; and 4) the type size should be appropriate for the size of the volume. (83 , 161 , 259 , 307 , 343 )