Eraser+Teen4+G1

 Before the invention of the rubber eraser, tablets of wax were used to erase lead/charcoal marks from paper. Bits of rough stone were used by various cultures to remove small errors from parchment or papyrus documents written in ink. It has been claimed that bread was, in the past, commonly used as an eraser; this is possible, but the bread would disintegrate, and would at that time most likely have been too costly to replace. On April 15, 1770, Joseph Priestley described a vegetable gum which had the ability to rub out pencil marks, and called it “rubber”. In 1770, Edward Nairne, an English engineer, is credited with developing the first widely-marketed rubber eraser for an inventions competition. He sold natural rubber erasers for the high price of 3 shillings per half-inch cube. According to Nairne, he inadvertently picked up a piece of rubber instead of bread, discovered rubber's erasing properties, and began selling rubber erasers. Incidentally, this was the first practical application of the substance in Europe. However, rubber had the same inconveniences as bread, since it was perishable and would go bad over the time. In 1839, inventor Charles Goodyear discovered the process of vulcanization, a method that would cure rubber and make it a durable material. Rubber erasers became common with this advent of vulcanization. On March 30, 1858, Hymen Lipman of Philadelphia, USA, received the first patent for put an eraser to the end of a pencil. It was later invalidated because it was determined to be just a composite of two objects than a new product.

  Rubber eraser    ﻿ Pencil eraser  