Set squares are drawing instruments used to create vertical, horizontal, and diagonal lines as well as certain angles. They may be shaped as squares, Ls, or triangles, although in American usage set ...

In the early '60's, all freshmen at Worcester Polytechnic Institute had to take a semester of mechanical drawing and another semester of descriptive geometry. So we all bought drafting sets and a ...

The triangles in the mathematics collections illustrate the products sold by leading American makers of drawing instruments, including Darling, Brown & Sharpe of Providence, R.I.; and Keuffel & Esser ...