No. 196. Dome Treatment. Vertical and horizontal division, resulting in panels. Villa Madama, Rome. [Alinari ] [Illustration: Photo] No. 197. Dome, St. Peter’s, Rome. Example of radial division. [Alinari ] pendants is really a continuous horizontal treatment in which the vertical direction is emphasised by way of contrast. The same principle is involved in the decoration of mouldings. Vertical features should be in alignment with adjacent and dominant details. [Illustration: No. 199. Frieze. Temple of Antoninus and Faustina, Rome. Horizontal direction suggested by Gryffons, with vertical contrast by Candelabra.] All kinds of elements can be employed in Frieze decoration, and as much interest and liveliness imparted as is compatible with the necessary repetition. _Borders_ Borders, with or without mouldings, may be considered as frames to the spaces they separate or enclose; in the latter case they are invariably uniform in width (except when used in Typography and illuminations, where some license is permissible). As borders are structural in suggestion, the elements employed should be simple and without that interest which is desirable in other positions. The detail to be used is largely determined by scale and position. When on a small scale, borders may be mainly composed of a series of lines spaced so as to suggest the various features of a moulded band, in which case it is essential that the same width be maintained throughout the length, while the lines are returned at the corners at mitral angles. This treatment can be elaborated by the introduction of other lines between those most widely spaced at right angles with the direction, and these can again be broken at intervals by rosettes or other simple forms. [Illustration: No. 200. Key-Pattern Borders.] [Illustration: No. 201. Interlacing Borders.] The well-known key-border is a continuous narrow band or line which traces out a labyrinth pattern by bending inwards at right angles and then returning to the original direction. This, in its simplest form, is an elaboration of adjacent squares in which a top and bottom line is alternately dispensed with. _Geometric Elements_ The simplest elements in border decoration are geometric in character. The border may be divided by straight lines intersecting at various angles, or by curves struck from equidistant centres, or by a combination of straight lines and curves. _The Undulate Line_ [Illustration: No. 202. Growth Line based on Geometric Curves.]