گونه‌شناسی الگوی چهارصفه در معماری ایرانی و سیر تحول آن

Iranian architecture follows various formal patterns, mostly had been worked in artistic pieces then worked to architectural structures. Deeply looking at motifs in artistic works and architectural plans, streaks of cosmological beliefs can be traced. Nonagon division of squares, "Chaharbagh" or "Chaharsofeh" plans can be among important ones. It seems that these patterns have been primarily used in the artistic motives such as pottery decorations before being evolved in the architectural forms. Nonagon division of square which was lately emerged in form of “nine-bay” plans can be found on the primitive motifs of Neolithic pottery decorations. Chaharbagh –four gardens- plan has been already illustrated on the Chalcolithic potteries which were found in Samarra before being used in landscape design of the historical era. However, proficiency of the Samarra potters in geometry and their awareness about the anatomy of some of the animals has been reflected in motives which were designed at the centre of the internal surface of the dishes. Some of these motives reminds the Chaharsofeh or four Ivan plans which is a typical design of the Iranian architecture in the later historical periods used in several palaces, caravanserais, schools and houses. The present paper attempts to investigate mostly known Chaharsofeh plan. Although there have been varieties of studies in Iranian architecture, but there is not appropriate research on Chaharsofeh plan that resulted to lack of sufficient knowledge on relevant typology. As a fundamental research, present study naturally can be counted a historic-descriptive investigation, where data collected bibliographically. Collections of evidence were comparatively studied, analyzed, and interpreted. Conclusions indicate that there were ancient cosmology in such design and architecture, except ecological considerations. From one hand, cosmological Tetragonal division of the world, and on the other hand ancient beliefs that resemble the earth as "Chahartagi" that tended to center despite of regarding cardinal orientations formed and flourished the design and similar ones. Studies on several valid historic texts indicate that "Chahartagh" label has been used for various monuments, however, it explain and describe an architecture embodiment, but as architectural pattern or a design label it never signal evidences. Chaharsofeh design is appropriately compatible to Iranian architecture and responded to varieties of functions, and at the same time, covered ecological and environmental requirements of architects. It is categorized within two groups first with yard and second without it. First group remained as "four porticos" design in characteristic standard from earlier formation to recent centuries. First samples of such designs were presented at Achamenid architecture at "Treasure' section of Persepolis and "No. 3 Building" at Dahaneh Qolaman. Later, it was worked at Parthian period at Assyria Palace with a vaulted type and at Sassanid period as well. During the Islamic period and specifically in 14th century, this plan was so common that a mosque could not be imagined otherwise. It was dominant model in numerous Iranian houses, caravanserais and schools in Iranian central plateau and introduced "Chaharsofeh Style" to Iranian architecture. Several schools and tombs somewhat followed the design. The other grope subdivided to two groups firstly, the general design multiply at number 5, while the other signals the structure embodiment in a nonagon division. Known domical structures generally related to first group. It was experienced firstly at formalities hall of Bishapur Palace, dated to earlier Sassanid times, and vastly was used at domical structures of later Islamic buildings of medieval periods. The second group is in difference with "introvert nonagon domes" pattern and multiplied at nine. It divided to two itself: some vary functionally with a focal dome and peripheral chambers and small Chaharsofehs, where from exterior there can be seen a small dome from each angle. Although designs on some Sassanid vessels confirm usage of the design in elite architecture of the period, the first examples of such designs come from Sassanid fire temples. It used at some mosques' plan, several baths, several pavilions and tombs in Islamic periods. Although, this architectural standard was developed in Sassanid period, glorious evolution of this architecture occurred in later Islamic period in a way that was never experienced before. Architects and designers of the Othmanid period, specifically “Senan” developed this style in the most magnificent way. Symbolic and advertising features of this architectural style of Othmanid period is significantly sensible in the mosques such as “Shahzadeh” and “Sultan Ahmad” and developed unique masterpieces in the introvert style. Examples of this style have been found with four domes at the four corners while the buildings structure has been divided into five sections. Symbolic examples of this type are the tombs of Samanid governors in Bukhara. At second group, nonagon type, there is relatively big Chaharsofeh with four vaulted chambers around central dome house. Several mountainous castles mountainous, plain and coastal Karvanisarais, and small road cafes also constructed on the design.