This regular recurrence of a unit over a surface in such a way as to lead the eye con sistently through all parts of the pattern is called rhythm, which is responsible for a great deal of the charm that obtains in all kinds of surface design.
Borders.— Borders, or designs used for limiting surfaces, are produced by the rhythmic repetition of a unit in one direction. (Fig. 12).
Lettering in Design.— Lettering forms the major motive in designs for monograms, book plates book-covers and posters. The alpha bets now generally used are the modern Gothic and Roman.
Monograms.— A monogram is a character consisting of two or more letters, interwoven In each of these kinds of design, what is termed the unit, or motive, is repeated in a particular mode. The unit of design is a simple decorative figure, either symmetrically arranged, or informally balanced about a vertical line. (Fig. 10).
All-over Patterns, as designs for textiles, cretonnes and wall-papers, are developed by the rhythmic repetition of a unit over a sur face in all directions. When the unit is re into one, usually the initials of a name or several names. Besides unity, balance and rhythm, which are essential in all surface design, the special principle governing a good monogram is intricacy. By this is meant the pleasing effect obtained by a happy interlacing or interweaving of the letters. The more subtle the interweaving, the more attractive the design. (Fig. 13). Unity in a monogram is best obtained by a proper distribution of the letters within any geometric surface as a square circle, kiteform, hexagon, etc. Mono grams are generally applied to jewelry, sta tionery and linen.
Bookplates.— A bookplate or aEx Libris* is the little label or plate put into a book by its owner. The designer must introduce into the bookplate as much as possible the char acter, taste, ambition or hobby of the person, for whose library the plate is designed. For instance, if the person is romantic,—knights, castles and brave deeds appeal to him — a decorative treatment of a castle would be ap propriate. The lettering, of course, plays the
most important part. It should be legible and in such a style as will suit the general idea, and must have a well thought out and im portant position. (Fig. 14).
Book-covers.— A design for a book-cover generally contains several lines of lettering, that is, the title and the name of the author, and an ornament. The ornament may be a purely decorative figure, or a decorative treat ment of a landscape, marine or figure com position, suggesting the contents of the book. All the lettering on the cover should he of the same style, and the title made con spicuous by the use of intense tones.
Posters.— A poster is a placard announc ing an event, or advertising an article. It is considered effective, naturally, when it attracts attention, and excites interest in the event announced or the article advertised. To im part this attractive power to his design, the poster designer makes use of either some catch phrase, or some peculiar pictorial decora tion, or a combination of both.
Bibliography.— Allonge,