P. stands for _particula_, a little part, and means so much as can be taken between the ends of two fingers. P. æq. stands for _partes æquales_, or equal parts. q. s. _quantum sufficit_, or as much as is sufficient. q. p. _quantum placit_, or as much as you please. s. a. _secundem artem_, or according to art. METAL RULES OR DASHES. Metal Rules or dashes, [⸺] like quadrates, are commonly cast from one em to three ems in length. When cast to line and join accurately, they may be used instead of brass rule. BRACES. Braces [⏞] are used chiefly in tables of accounts, botanical and geological tables, and similar matter. They are placed before or after a series of items of similar import; and are sometimes used horizontally in the margin, to cut off a chronological or other series from the proper notes or marginal references of the work. Braces, two, three, and four ems in length, are now cast for all sizes of common type. _Middles_ and _ends_ are also cast, [[symb]] which can be filled out with dashes to any length required for the brace. Middles and ends are convenient in genealogical tables, in which they are used the flat way, and in which the directing point is not always in the middle. Brass braces of any length, for music and jobbing purposes, are furnished by type-founders. SPACES. Spaces are short blank types, and are used to separate one word from another. To enable the compositor to space even and to justify with nicety, they are cast to various thicknesses,—viz. five to an em, [[symb]] or five thin spaces; four to an em, [[symb]] or four middle spaces; three to an em, [[symb]] or three thick spaces; and two to an em, [[symb]] or two en quadrates, which may with propriety be reckoned among the number of spaces. Besides these, there is what is called the hair-space, which is cast extremely thin, and is found useful in justifying lines and assisting uniformity in spacing. TWO-LINE LETTERS Are equal in depth to two lines of the type in which they are to be used, and of proportionate width. They form the almost only proper type for principal lines in title-pages, and are used at the beginning of chapters and newspaper advertisements. QUADRATES. An em quadrate [■] is a short blank type, in thickness equal to the square of the letter of the fount to which it belongs; an en quadrate [▮] is half that size. The first line of a paragraph is usually indented an em quadrate; but when the matter is leaded or the measure is wide, an em and en, or two or even three ems may be used. An em quadrate is the proper space after a full-point when it terminates a sentence in a paragraph. En quadrates are generally used after the semicolon, colon, &c., and sometimes after an overhanging letter. They are useful in spacing.