Theodore Schwann  (1810-1882)

Theodore Schwann was a German physiologist who, with his friend Matthias Scheiden, first proposed cell theory – that the cell as the basic unit of all living things.

The cells that make up the myelin sheath which surrounds the axons of most neurones, are named after Schwann.  This picture shows living Schwann cells growing in culture.  

Schwann also examined the question of spontaneous generation.  He showed that heat would destroy the ‘infusoria’ needed for purtrefaction.  To do this he passed air through red-hot tubes to sterilise it and showed that it would not cause sterile broth to putrify.   Opponents argued that the heated (calcined) air was unable to support respiration.

Bibliography

Roy Porter The Greatest Benefit to Mankind, Harper Collins 1997