« Vitr. 9.0 | Vitr. 9.0 | Vitr. 9.1 | About This Work »
6Pythagoras demonstrated the method of forming a right angle without the aid of the instruments of artificers: and that which they scarcely, even with great trouble, exactly obtain, may be performed by his rules with great facility. Let three rods be procured, one three feet, one four feet, and the other five feet long; and let them be so joined as to touch each other at their extremities; they will then form a triangle, one of whose angles will be a right angle. For if, on the length of each of the rods, squares be described, that whose length is three feet will have an area of nine feet; that of four, of sixteen feet; and that of five, of twenty-five feet:
« Vitr. 9.0 | Vitr. 9.0 | Vitr. 9.1 | About This Work »