Screw-cutting lathe name "screw-cutting lathe" carries a taxonomic qualification on its use—it is a term of historical classification rather than one of current commercial machine tool terminology. Early lathes, many centuries ago, were not adapted to screw-cutting. Later, from the Late Middle Ages until the early nineteenth century, some lathes were distinguishable as "screw-cutting lathes" because of the screw-cutting ability specially built into them. Since then, most metalworking lathes have this ability built in, but they are not called "screw-cutting lathes" in modern taxonomy. The screw has been known for millennia. Archimedes devised the water screw, a system for raising water. Screws
Trammel of Archimedes Trammel of Archimedes A trammel of Archimedes is a mechanism that generates the shape of an ellipse. It consists of two shuttles which are confined ("") to perpendicular channels or rails and a rod which is attached to the shuttles by pivots at fixed positions along the rod. As the shuttles move back and forth, each along its channel, the end of the rod moves in an elliptical path. The semi-axes "a" and "b" of the ellipse have lengths equal to the distances from the end of the rod to each of the two pivots. An ellipsograph is a trammel