Robert Hooke, the Man Who Discovered Cells

An illustration of a flea drawn by Robert Hooke in Micrographia, 1665. Hulton Archive / Getty Images

Robert Hooke was a 17th century "natural philosopher" -- an early scientist -- noted for a variety of observations of the natural world. But perhaps his most notable discovery came in 1665, when he looked at a sliver of cork through a microscope lens and discovered cells. 

Early Life

Hooke, the son of an English minister, was born in 1635 on the Isle of Wright, an island off the southern coast of England.

As a boy he enrolled at Westminster School in London, where he studied classics and mechanics. He later went on to Oxford, where he worked as an assistant to Thomas Willis, a physician and founding member of the Royal Society, and worked alongside Robert Boyle, known for his discoveries on gases.

Hooke himself went on to join the Royal Society.

Observations and Discoveries

Hooke isn't as well known as some of his contemporaries. But he did make a place for himself in the history books when he looked at a sliver of cork through a microscope and noticed some "pores" or "cells" in it. Hooke believed the cells had served as containers for the "noble juices" or "fibrous threads" of the once-living cork tree. He thought these cells existed only in plants, since he and his scientific contemporaries had observed the structures only in plant material.

Hooke recorded his observations in the Micrographia, the first book describing observations made through a microscope.

The drawing to the top left, of a flea observed through his microscope, was created by Hooke. Hooke was the first person to use the word "cell" to identify microscopic structures when he was describing cork.

His other observations and discoveries include:

  • Hooke's Law -- a law of elasticity for solid bodies, which described how tension increases and decreases in a spring coil
  • Various observations on the nature of gravity, as well as heavenly bodies such as comets and planets.
  • The nature of fossilization, and its implications for biological history.

Hooke died in 1703, having never married or borne children.