John Needham
John
Turberville Needham
FRS (September 10, 1713 – December 30, 1781) was an English biologist and Roman Catholic priest.
He was first exposed to natural philosophy while in school and later published a paper which, while the subject was mostly about geology, described the mechanics of pollen and won recognition in the botany community.
He did experiments with gravy and later, tainted wheat, in containers. The experiments consisted of briefly boiling a broth mixture and then cooling the mixture in an open container to room temperature. Later, the flasks would be sealed, and microbes would grow a few days later. Those experiments seemed to show that there was a life force that produced spontaneous generation. Needham theorized that if he took chicken broth and heated it, all living things in it would die. After heating some broth, he let a flask cool and sit at a constant temperature. The development of a thick turbid solution of microorganisms in the flask was strong proof to Needham of the existence of spontaneous generation.1 Today, we know that the boiling time was insufficient to kill any endospores of microbes and the cooling of flasks left open to the air could cause microbial contamination. We would conclude that Needham did not use proper sterile technique. His experiments were challenged and repeated by Lazzaro Spallanzani, an Italian scientist. Using a slightly different protocol (with a longer boiling time), Spallanzani did not have any microbes grow in his sealed flasks, contradicting the findings of Needham.
He is frequently believed to be an Irish Jesuit priest, a myth which was created by Voltaire during a feud regarding spontaneous generation in which Voltaire was against Needham and his theories.
He was a member of the Royal Society, having become a member in 1768. He was the first Catholic priest to become a member.
Needham's experiments with the spontaneous generation of life were discussed by French Enlightenment philosopher Baron d'Holbach in his book, the System of Nature.
References
1. © 2003 - 2006 The Microbial World.
http://www.microbiologytext.com/index.php?module=Book&func=displayarticle&art_id=27
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