Wednesday, April 16, 2008

Wandom Wednesday

Hymen Lipman is the first person credited with the combination of pencil and eraser. This happened March 30, 1858.

  • Lipman's invention took place of about one-third of the pencil.
  • To "expose" the eraser, you had to sharpen the rubber end.
  • Lipman said being able to sharpen the eraser made it more useful for erasing lines near other lines.
  • Before India invented the rubber eraser, people used rolled up pieces of white bread.
  • An English engineer, Edward Naime, invented the eraser in 1770.
  • Because rubber would rot over time, Charles Goodyear's invention of vulcanization in 1839 made the rubber stay preserved.
  • Modern erasers are either made with a vulcanized combination of rubber and pumice, or with pumice and vinyl, which does not need vulcanization.

No comments:

Blog redesigned by Amy, a redeemed sheep | Template Design | Elque 2008