1561. Narrow terraces are entirely occupied as promenades, and may be either gravelled or paved; and different levels, when they exist, connected by inclined planes or flights of steps. Where the breadth is more than is requisite for walks, the borders may be kept in turf with groups or marginal strips of flowers and low shrubs. In some cases, the terrace-walls may be so extended as to enclose ground sufficient for a level plot to be used as a bowling-green or a flower-garden. These are generally connected with one of the living-rooms, or the conservatory, and to the latter is frequently joined an aviary and the entire range of botanic stoves. Or, the aviary may be made an elegant detached building, so placed as to group with the house and other surrounding objects. A curious structure of this sort (fig. 269.) was designed by Repton for the grounds of the Pavilion at Brighton.