Mechanical pencil

A mechanical pencil (US English) or a propelling pencil (UK English) is a pencil with a replaceable and mechanically extendable solid pigment core called a "lead" /ˈlɛd/. The lead, often made of graphite, is not bonded to the outer casing, and can be mechanically extended as its point is worn away. Other names include automatic pencil, drafting pencil, technical pencil, click pencil, clutch pencil (Indian English), leadholder, pen pencil, lead pencil (Bangladeshi English), and pacer (or spacer).

Mechanical pencils are used to provide lines of constant width without sharpening in technical drawing and in writing quick neat writing. They have also been used for fine-art drawing.

Mechanical pencils were first used in the 18th century, with many designs patented in the 19th and 20th centuries.

Conrad Gesner described a leadholder pencil in 1565, but the lead had to be manually adjusted to sharpen it. The earliest extant example of a mechanical pencil was found aboard the wreckage of HMS Pandora, which sank in 1791.

The first patent for a refillable pencil with lead-propelling mechanism was issued to Sampson Mordan and John Isaac Hawkins in Britain in 1822. After buying out Hawkins' patent rights, Mordan entered into a business partnership with Gabriel Riddle from 1823 to 1837. The earliest Mordan pencils are thus hallmarked SMGR. After 1837, Sampson Mordan ended the partnership with Riddle and continued to manufacture pencils as "S.MORDAN & CO". His company continued to manufacture pencils and a wide range of silver objects until World War II, when the factory was bombed.

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