Jāmi` al-mabādi` wa-’l-ghāyāt fī `ilm al-mīqāt (Collection of the principles and objectives in the science of timekeeping) is a comprehensive encyclopedia of practical astronomy, written in Cairo 1276-82. It was a standard reference work on spherical astronomy and astronomical instrumentation.  It was a work of intermediate to advanced level intended for active and apprentice muwaqqits and for specialists of timekeeping and instrumentation in Mamluk Egypt and Syria, Rasūlid Yemen, and Ottoman lands. The Jāmi` is made up of 4 books on the following topics: 1) On calculations in 67 chapters. 2) On the construction of instruments in 7 parts. Part 1 concerns graphical methods in spherical astronomy and gnomonics. Parts 2-7 treat the construction of portable dials, fixed sundials, trigonometric and horary quadrants, spherical instruments, instruments based upon projection, and observational and planetary instruments. 3) On the use of selected instruments in 14 chapters. 4) The work ends with a “quiz”  or series of questions and answers  in 4 chapters, whose aim is to train the mental abilities of the students. (See F. Charette, BEA)