Title: The Book of Instruction on Deviant Planes and Simple Planes

Description

This manuscript is a work on practical astronomy and the drawing of the circle of projection and related concepts from spherical trigonometry. It is rich with geometric diagrams, tables of empirical observations, and computations based upon these observations. An interesting feature of the manuscript is the appearance on the margins of the cover, and on several pages in the manuscript, of edifying verses, proverbs, and witty remarks. One reads, for example, “It is strange to find in the world a jaundiced physician, a dim-eyed ophthalmologist, and a blind astronomer.” Most of the remarks applaud the virtues of silence. The manuscript is dated 1153 A.H. (1740).