What do you call this type of pencil?
Mechanical pencil? Propelling pencil? In Japan most of my students call it a Sharp pencil.
This type of pencil was invented in Britain in 1822 by Sampson Mordan and Gabriel Riddle.
The mechanical pencil became popular in Japan and in 1915 Tokuji Hayakawa first made the type of mechanical pencil that is still used today. He called it the Ever Ready Sharp Pencil.
At first sales were small, but after a few years sales suddenly boomed. Hayakawa started a company which he named Sharp. This is the origin of the world-famous electronics company which now makes everything from fridges to Aquos TVs.