Hooke and the piece of cork

In 1665 Robert Hooke looked at a section of cork through a microscope he had built himself. What he saw that day gave biology a word it still uses.

Figure to be added

Figure 6.1 — Robert Hooke, the microscope he used, and the cells of the cork section.

What he saw

Across the whole section were small compartments packed together like the cells of a honeycomb, each one separated from the next by a definite boundary. He gave those compartments a name.

Cells

The compartments Hooke saw in the section of cork were named by him cells.

This was an observation, not a theory. Hooke said only what he could see — he did not claim that every living thing is built this way. That claim took another hundred and seventy years or so.

The word stayed

Hooke had named the compartments in a piece of cork. But when hundreds of other living things were later put under a microscope, the same kind of unit turned up everywhere. So his word became the name of the basic unit of life itself.