22 The Existence of Cells
Microscopes were invented in the late 1590s. By 1660 only a few had been built that
were able to magnify objects 100 times normal size. As microscopes became more powerful, they maintained focus on only a tiny sliver of space and were increasingly more difficult
to focus and to use.
Hooke was hired onto the staff of the Royal Society (an early English scientific organization) in 1660 and soon began a long series of microscopic studies. By 1662 he had helped
design a 300-power microscope, which he used to examine the microscopic structure of
common objects. Using this microscope and his artistic talent, Hooke created the first detailed studies of the microscopic world, rendering with lifelike accuracy the contours of a
fly’s compound eyes, the structure of a feather, and a butterfly’s wing. He also drew and
identified a series of microscopic bugs.
In 1664 Hooke turned his microscope onto a thin sheet of dried cork and found it to be
composed of a tightly packed pattern of tiny rectangular holes. Actually, cork has large,
open cells. That’s why Hooke was able to see them at all. The cells of other plants and animal tissue he studied were all too small to be seen through his microscopes.
Hooke called these holes cells (the Latin word for small chambers that stand in a
row—as in prison cells). These cells were empty because the cork was dead. Hooke correctly suspected that, while living, these had been filled with fluid.
The name “cell” stuck. More important, the concept galvanized biologists. The living
world was constructed of countless tiny cells stacked together like bricks in a wall. The entire field of biology shifted toward a study of cell structure and cell function.
Fun Facts: Cell biology is the only science in which multiplication
means the same thing as division.
More to Explore
Dyson, James. A History of Great Inventions. New York: Carroll & Graf Publishers,
2001.
Headstrom, Richard. Adventures with a Microscope. Mineola, NY: Dover Publications, 1997.
Inwood, Stephen. The Forgotten Genius: The Biography of Robert Hooke. San Francisco: MacAdam/Cage Publishing, 2005.
Jardine, Lisa. The Curious Life of Robert Hooke. New York: HarperPerennial, 2005.
Oxlade, Chris. The World of Microscopes. New York: Usborne Books, 1999.
Suplee, Curt. Milestones of Science. Washington, DC: National Geographic Society,
2000.
Yenne, Bill. 100 Inventions That Shaped World History. New York: Bluewood Books,
1998.