the summer pleasure gardens of the emir. Salmerón Escobar notes that the later planting of deciduous elms obscures the overall perception of the layout, so a better reading of the original landscape is given in winter when the trees are bare. Architecture General design The design and decoration of the Nasrid palaces are a continuation of Moorish (western Islamic) architecture from earlier centuries but developed their own characteristics. The combination of carefully-proportioned courtyards, water features, gardens, arches on slender columns, and intricately-sculpted stucco and tile decoration gives Nasrid architecture qualities that are described as ethereal and intimate. Walls were built mostly in rammed earth, lime concrete, or brick and then covered with plaster, while wood (mostly pine) was used for roofs, ceilings, doors, and window shutters. Buildings were designed to be seen from within, with their decoration focused on the inside. The basic unit of Nasrid palace architecture was a rectangular courtyard with a pool, fountain, or water channel at its center. Courtyards were flanked on two or four sides by halls, often preceded by arcaded porticoes. Many of these structures featured a mirador, a room projecting from the exterior commanding scenic views of gardens or of the city. Buildings were designed with a mathematical proportional system that gives them a harmonious visual quality. The layout of the courtyards, the distribution of windows, and the use of water features were designed with the climate in mind, cooling and ventilating the environment in summer while minimizing cold drafts and maximizing sunlight in winter. Upper-floor rooms were smaller and more enclosed, making them more suited for use during the winter. Courtyards were usually aligned in a north-south direction which allows the main halls to receive direct sunlight at midday during the winter, while during the summer the higher midday sun is blocked by the position and depth of the porticos fronting these halls. Architects and poets Little is known about the architects and craftsmen who built the Alhambra, but more is known about the Dīwān al-Ins͟hā''', or chancery. This institution seems to have played an increasingly important role in the design of buildings, probably because inscriptions came to feature so prominently in their decoration. The head of the chancery was often also the vizier (prime minister) of the sultan. Although not exactly architects, the terms of office of many individuals in these positions coincide with the major phases of construction in the