Discusses the properties and types of triangles, explaining that a triangle is a closed figure with three sides and angles. It categorizes triangles into equilateral, isosceles, scalene, obtuse, right ...

Includes facsimile of the 1533 Latin edition (which was edited by Johann Schöner), with t.p. reading: Doctissimi viri et mathematicarum disciplinarum eximii professoris Ionnis de Regio Monte De ...