The prince was working at the lathe and after glancing round continued his work.
A sheet of metal set revolving at a high speed in a lathe is bent over into cup-shaped forms, with numerous mouldings, by a blunt hardened tool.
Motion in either direction is thereby obtained, and a considerable variation in the speed of rotation can be obtained by providing a cone pulley on the countershaft, which drives the cone pulley secured to the lathe E FIG.
The dimensions of the pulleys are generally so arranged that the return motion of the lathe spindle is faster than the forward motion.
The sphere is then coated with plaster or whiting, and when it has been smoothed on a lathe and dried, the lines representing meridians and parallels are drawn upon it.