What Are Pencils with Erasers?

Who Thought of Putting an Eraser on a Pencil? Pencils with erasers are an American phenomenon. The first patent on an integral pencil and eraser got assigned in the United States on March 30, 1858, to Joseph Reckendorfer of New York City.

For an invention by Hymen L. Lipman of Philadelphia, who devised a method for enlarging the groove in the pencil sheath intended for the lead core so that it would accept an eraser.

Back in the 1850’s, pencils and erasers had been in use, but they weren’t fastened together. If you made a mistake with a pencil, you had to find an eraser.

In 1858, Rechendorfer took out a patent on his idea. His pencils became very popular. This design though failed to catch on in many countries.

If you’re traveling outside the United States, you may notice that it’s hard to find a pencil with an eraser on it.

Pencil erasers are made of rubber mixed with pumice for erasing power. They crumble gradually when used. An eraser that does not crumble smears the marks without removing them completely.

How long does a pencil eraser last? On average one of those white erasers lasted about three weeks. Those old red rubber ones I would lose or misplace long before wearing out.

Are pencil erasers edible? An eraser is a piece of rubber used to remove pencil drawings. Erasers are not poisonous if swallowed, but larger pieces can be a choking hazard.

Content for this question contributed by Seth Kopchak, resident of Pittsburgh, Pennsylvania, USA