Hundred Great Muslims

186 Hundred Great Muslims
wanted to construct an armillary sphere, which would be finest and best that
had yet been made, it was to the Arabsthat he turned for information"
The principal research carried on in the Maragha observatory which lasted
for two generations only, related to the compilation of "AI Zij-al-llkhani"
better known as "The Ilkhanian Tables ': which earned great popularity throughout
the East, including China. This Table was compiled by Nasir al-Din Toosi
after 12 years of hard research and was completed in 1272 A.C. The original
text was probably written in Persian. This work is divided into four books
namely, (1) 'Chinese, Greek, Arabic and Persian Chronology, (2) Motions of the
Planets, (3) Ephemerides, (4) Astronomical Observations. This Table was
translated into Arabic and severalcommentaries were written on it.
His other important astronomical works regarding calendar are
(I') 'Mukhtasar fi Ilm al Tanjim wa Marifat al-Taqwim' (Summary of Astrology
and of the Calendar) which is extant in Persian; and (2) 'Katab al-Barifi Ulum
al-Taqwim wa Harakat al Aflak wa-Ahkam al Nujum '(The excellent book on the
Calendar, the Movement of the Spheres and Judicial Astrology).ThisAstrological
treatise 'Kitab-i-si-Fasl,' is a work of high order.
Only next to astronomy stands Nasir al-Din's contribution to mathematics.
He has left behind him immortal works on geometry and trigonometry. He
edited most of the ancient mathematical works numbering 16, which included
four books of the Muslim period. He wrote four treatises, on arithmetic and
algebra, including "AI Mukhtasar bi Jami al Hisab bil Takht wal Turab",
(Summary of the whole of Computation with Table and Earth) and 'Kitab al
Jabr wal Muqabala' (Treatise on Algebra). The first one is extant in Arabicand
Persian.
He is equally important as a geometer. He wrote no less than fifteen
treatises on geometry, which included his 'AI Usul ul Maudua' (Treatise on
Euclids Postulates); 'Qawaid~al·Handasa' (principles of Geometry) and "Tahrir
al Usual" (the two Reductions of the Elements of Euclid) in which, contrary to
theprinciple followed by Euclid, he multiplied the special cases
Nasir al-Din Toosi played no small part in the advancement of trigonometry.
Hisworks on trigonometry marked the culmination of the progressin the
subject. He is the author of the 'Kitab Shakl a/ Qatta' (A treatise on Quadrilateral)
an extremely original work in whichtrigonometry has been treated
independently of astronomy. The book dealing with spherical trigonometry is
very .comprehensive and perhaps the best work on the subject written during
the mediaeval times. It was translated into French and edited by Alexandre
Cara Theodory Pasha in 1891. Writing in the Legacy of Islam, Carra De Vaux
says, "Trigonometry, plane or spherical, is now well established and finds in
this book its first methodically developed and deliberate expression". This
treatise of Nasir al-Din had a deep influence over the mathematicians of both
the East and, West who based their trigonometrical researches on this book.