Mechanical pencil
device · 1790 · Industrial Revolution
A pencil with a retractable lead (late 18th century; Hawkins and Mordan’s patent, 1822).
Inventors: Sampson Mordan, John Isaac Hawkins.
What it is made of
- Spring — has part. A feed mechanism.
Principles and materials it uses
- Silver — is made of. Early mechanical pencils were silver.
- Graphite — is made of. The lead is graphite.
History: what it evolved from and what it influenced
- Pencil — evolved from. A retractable lead.