Sultan grammar—uses the same words for both women and men. However, this styling misconstrues the roles of wives of sultans. In a similar usage, the wife of a German field marshal might be styled "Frau Feldmarschall" (similarly, in French, constructions of the type "madame la maréchale" are quite common). The female leaders in Muslim history are correctly known as "sultanas". However, the wife of the sultan in the Sultanate of Sulu is styled as the "panguian" while the sultan's chief wife in many sultanates of Indonesia and Malaysia are known as "permaisuri", "Tunku Ampuan", "Raja Perempuan", or "Tengku Ampuan". The queen
Arabic mile If al-Farghani used the legal cubit as his unit of measurement, then an Arabic mile was 1995 meters long. If he used al-Ma'mun's surveying cubit, it was 1925 meters long or 1.04 modern nautical miles. During the Umayyad period (661–750), the "Umayyad mile" was roughly equivalent to , or a little more than two kilometers, or about 2 biblical miles, for every Umayyad mile. Around 830 AD, Caliph Al-Ma'mun commissioned a group of Muslim astronomers and Muslim geographers to measure the distance from Tadmur (Palmyra) to Raqqa, in modern Syria. They found the cities to be separated by one degree