Aye, there’s the rub, as it were. Lukowski’s cone-tipped electric eraser, he argued, could better handle the fine detail. An electric eraser could also be a timesaver. In the days before ...

8. The little erasers on pencil ends are known as "plugs." Yep. And those small bands of metal that contain the plugs are called "ferrules." 10. There are such things as electric erasers.

There are some inventions that look completely pointless to the untrained eye: who would ever need a motorized garbage can, an electric pencil sharpener or a battery-powered eraser? Quite often ...