TYPOGRAPHY is the art of printing. (See also the articles PRINTING, PRINTING TYPE and CALLIGRAPHY.) It has as its first object not ornament, but utility. The printer must never distract, even with beauty, the reader from his text. In the printing of books there is less room for individuality of style than in the typography of propaganda. The laws of typography in books in tended for general circulation are based upon (a) the essential nature of alphabetical writing; (b) the force of tradition. But strict as the conventions are, there is not, and can never be, a rigid character of typography applicable to all books produced in a given geographic or ethnic area ; or a universal formula accept able to all books printed in Roman types. The strength of tradi tion expresses itself in the details of book arrangement and these vary widely. Certain laws of linear composition are, however, obeyed by all printers who use the Roman letter.
A fount of Roman type consists of (I) Roman: CAPITALS, SMALL CAPITALS, lower case, : . " ; I 2 3 4 5 etc () ; and (2) Italic: CAPITALS, lower case. In addition to these, as necessary adjuncts, the printer possesses (3) spaces; (4) leads, (5) straight lines of metal known as rules, and (6) a collection of mobile ornaments, head- and tail-pieces, flowers, decorated initial letters, vignettes and flourishes, wood blocks of borders, etc. Another decorative medium at his command lies in his use of (7) colour (red being the most widely used). For emphasis he possesses (8) special types of notably heavy face, and may use colour for the same purpose. (9) Space is another valuable element, mar gins, blanks, etc. being filled in with what are known as "quota tions." Finally (io) there is the nature (colour, weight and tex ture) of the paper.
Composition is the selection and arrangement of all these ele ments; Imposition is the due placing of the composition upon the sheet ; Printing comprises the press-work, securing a perfection of register (backing up), the quality and crispness of inking. Typography, therefore, controls composition, imposition and paper. The paper (q.v.) must be of a character capable of ex pressing the value of the composition. The margins must be pro portionate to the area of the text, allowing convenient space for thumbs and fingers at the side and bottom of the page. The me
diaeval margins as adopted by the Kelmscott Press, are handsome and agreeable in certain books, but, are neither agreeable nor convenient in other books, e.g., where the page dimension is neces sarily small or narrow, and the book is to be carried in the pocket. For this and other books, the type may well be centered on the measure of the page, and slightly raised above ocular centre.
fundamental principles of page-composi tion are deducible from the ocular facts of alphabetical printing in the Roman letter. The eye cannot, with ease, read pages of words composed of letters designed with sharply contrasting thicks and thins. Nor can the eye agreeably read a mass of words composed even in a rightly constructed letter, unless the line is kept to a certain maximum length ; that is to say, the reader's eye cannot comfortably seize more than a certain number of words in any given size except in a proportionate length of line. Nor can a reader comfortably seize a letter, a word or a line, unless the printer's setting is related to the reader's normal habit of vision when holding a book for reading. The typographer's re spect for these principles will generally protect the reader from the risk of "doubling" (that is, reading the same line twice), or from being given a book in a large and "staring" type.
The average number of words which the reader's eye can con veniently seize is between Io and 12 (some 48 characters). The typographer, while exerting himself to the utmost to respect this ocular limitation, may often be confronted with certain conditions which make it impossible for him to secure a type of the right related size. He is often forced to the use of a small type, and in order to obviate the risk of "doubling," he inserts leads between the lines of type and thus increases the space between them. The practice of leading, denounced in certain quarters, is an essential necessity. The typographer, therefore, in making the best use of his material, must make legitimate use of leads. It may be added, too, that in certain compositions, leads produce a happy effect ; and in not a few cases, their absence may ruin a composition set even in a relatively large type.