عنوان مقاله :
The Gnomonic Application of Sharaf alDīn alṬūsī’s Linear Astrolabe
پديد آورندگان :
Nikfahm Khubravan ، Sajjad McGill University - Institute of Islamic Studies
كليدواژه :
Astrolabe , Gnomon , Kamāl al , Dīn Ibn Yūnus , Linear astrolabe , Sundial. , Dīn al , Ṭ Astrolabe , Gnomon , Kamāl al , Dīn Ibn Yūnus , Linear astrolabe , Sharaf al , Dīn al , Ṭūsī , Sundial
چكيده فارسي :
The linear astrolabe was invented by Sharaf alDīn alṬūsī (fl. c. 1180) and although several Arabic monographs on the subject have reached us, none have received sufficient scholarly attention. As a result, one of the most important features of Ṭūsī’s invention, the gnomonic application, remains unknown. Based on an analysis of all known monographs on the linear astrolabe, this paper will discuss the gnomonic application of the linear astrolabe, which is an alternative to the azimuth lines typical of the plane astrolabe. We will also consider the potential role of Ṭūsī’s pupil, Kamāl alDīn ibn Yūnus (d. 1242), in the improvement of this instrument. Finally, after surveying the available manuscript copies of the abovementioned monographs, we present a full edition and translation of one such text and an edition and translation of one chapter, on the gnomonic application, from another text.
