Study and Analyze of the Form and Structure of Inscriptions on Brick Minarets of the Ghaznavid and Seljuk Periods in Khorasan

Abstract
Construction of high and cylindrical minarets has been expanded in Iran from the fifth century. Many of them are symbolic, political, memorial and military. These minarets were a kind of guide or map for caravans in day and night, and along with religious minarets-which are mainly built in mosques-they contain inscriptions and arrays that wish health and stability for travelers. Most of the inscriptions are written in Kufic script, including simple square Kufic, corrugated Kufic, floriated Kufic, etc. which is presented in different dimensions and various proportions of bricks and in combination with geometric or plant motifs. Khorasan, with its long history before and after the advent of Islam, has been one of the important governmental states. This region has protected the guide minarets of Firoozabad, Khosrow Gard Sabzevar, Ayaz and Karat from the ravages of time from the Ghaznavid and Seljuk periods. Geometric letters of Kufic script and its integration with motifs in Ghaznavid and Seljuk periods has left a wide range of arrays on architectural works with the help of Iranian taste. Since there is a direct and coordinated relationship between the location choice for construction of the minaret and the use of the minaret, the reason for construction of this type of monument can be considered its specific function, which is generally divided into two categories:

A) The minaret for the call to prayer of the mosque. B) Leader minaret, which has been built next to the main and secondary roads of silk way, old caravanserais and wide plains for tracking and finding the way. Remaining minarets with these two uses include Khosrow Gard Minaret in Sabzevar, Arsalan Jazeb minaret in Sang Bast, Firoozabad Minaret in Bardaskan, Madreseh Minaret in Golshan, Karat Minaret, Semnan Minaret, two minarets of Hazrat Reza (AS), Ghazni Minaret which belong to the reign of Mahmoud Ghaznavi period, the minaret of Sultan Massoud the third in Ghazni, the minaret of Bastam and the minaret of Jam in Afghanistan.

The purpose is to re-read the inscriptions and analysis of form and written structure dominating the inscriptions of the minarets Firoozabad, Khosrow Gard, Ayaz and Karat (which is all leading type) remained from the Ghaznavid and Seljuk periods in Great Khorasan region. Therefore, this article seeks to answer the question: What was the concept of Firoozabad, Khosrow Gard, Ayaz and Karat minarets and what were the structural and formal features of them? The research method is descriptive and analytical and data collection is based on library data and especially field surveys.
The turning point of the article is recognizing the inscriptions and analyzing their form and structure in mentioned minarets, which have received less attention or some parts of the inscriptions have not been read correctly in the previous sources, which has been taken care of in this essay. The findings show that the inscriptions have a historical content. Kufic script can be well combined with other designs and calligraphic art and connected to the main body of the inscription in terms of structure and design. The Kufic inscriptions of the minarets of Firoozabad Bardaskan, Khosrow Gard, Ayaz and Karat are informative due to the nature of their use. Architects and scribes have used brick materials with similar dimensions of 5*5* 25 plus gypsum mortar, lime and mortar.
The location of installation for all four mentioned minarets is the upper half of the minaret. In response to the first question, it can be said that the content of the inscription on the minarets of the Ghaznavid and Seljuk periods in Khorasan should be placed in three categories: historical, founders, architects and builders, and religious. The historical content of the inscriptions is included in mentioning the year of construction of the building, which is generally recorded at the end of the inscription. Supporters, founders, and acquaintances are mentioned in the form of the names of individuals at the beginning of the inscriptions, most likely from court officials and relatives who were able to support such works, or from well-known families or the governor's order.
This issue is clearly mentioned in Khosrow Gard minaret that after the name of the person the adjective Wali Amir al-Momenin or Sheikh is added, which indicates the high political and scientific position of that person. Also, the name of the architect and the builders are mentioned in some minarets such as Firoozabad minaret, which shows their high position in the design of the project. The third category is religious themes. This issue has been done on the Firoozabad minaret in the form of repeating the word Muhammad on the whole body of the building in a masterful way, which was achieved for the first time in this monument.
Perhaps this was parallel with the policy of the government, which has shown the dominance of Sunni beliefs over such a huge structure. In addition, the inscription of the Ayaz minaret invites Muslims to perform righteous deeds on the people. It should be said that most of the inscriptions contain the names of the founders who reminded their power and politics to the passers-by and caravans.
In response to the second question, it should be said that the designers and creators of these inscriptions have tried to preserve the rhythm of the inscription by using various and creative designs of letters, in each minaret. In the writing system of four minarets, only Firoozabad minaret is combined with plant motif in its writing system and Khosrow Gard minaret is combined with brick curved shapes. In implementing the combination of writing system and plant motifs, the scribe has figured out a harmonious and complex structure in Firoozabad minarate. The rhythm in Firoozabad minaret is mainly kept by the system of floral motifs and vertical letters. Single and pair vertical elongated combinations, circular and toothed inscriptions play an important role in the balance and rigidity of the inscription. Proportion of width and length of the inscription in the writing system has shown the two-by-one space next to the system of plant motifs. In Khosrow Gard minaret inscription, the writing system is combined with simple curved shapes and the vertical letters are in charge of keeping the rhythm. The inscription has a straightforward and simple design and alphabets Lam and Alif (letters in Arabic) are used for keeping rhythm.
The proportion of the width of the inscription dominates the writing system rather than the curved forms. In contrast to these two, Ayaz inscription does not have a proper uniformity and the inscription is done at the beginning and end with compression, which shows lack of precise design or acceleration in work. This inscription includes only a simple writing system and the curved structure of the letters is also used in the design. In Karat inscription the letters have been executed with more roughness, although the less width of the inscription and the legibility has been involved in this issue. Proportions and composition of letters and words have followed the principle of width equal to the length of a brick. The vertical letters in the four mentioned minarets have created a visual balance with the help of vertical words, Alif, Lam and 'La' (in Arabic) and the use of letters along with creating equal distances in the overall composition as well as the use of Axons. Letters and words in some of them, such as the minaret of Firoozabad, are prolific and elegant, and in the minaret of Ayaz, it is designed with more elegance. The difference between the inscriptions is in using different types of Kufic scripts such as floriated Kufic calligraphy in Khosrow Gard and Firoozabad minarets and simple Kufic calligraphy in Ayaz minaret and Kufic with leaf arrays calligraphy in Karat minaret and shows the principle of diversity in this historical period.