Italian Lazzaro Spallanzani (1729-1799), one of the most
picturesque figures in the history of science. He was not
educated either as a scientist or physician, devoting, himself at
first to philosophy and the languages, afterwards studying law,
and later taking orders. But he was a keen observer of nature and
of a questioning and investigating mind, so that he is remembered
now chiefly for his discoveries and investigations in the
biological sciences. One important demonstration was his
controversion of the theory of abiogenesis, or "spontaneous
generation," as propounded by Needham and Buffon. At the time of
Needham's experiments it had long been observed that when animal
or vegetable matter had lain in water for a little time--long
enough for it to begin to undergo decomposition--the water became
filled with microscopic creatures, the "infusoria animalculis."
This would tend to show, either that the water or the animal or
vegetable substance contained the "germs" of these minute
organisms, or else that they were generated spontaneously. It was
known that boiling killed these animalcules, and Needham agreed,
therefore, that if he first heated the meat or vegetables, and
also the water containing them, and then placed them in
hermetically scaled jars--if he did this, and still the
animalcules made their appearance, it would be proof-positive
that they had been generated spontaneously. Accordingly be made
numerous experiments, always with the same results--that after a
few days the water was found to swarm with the microscopic
creatures. The thing seemed proven beyond question--providing, of
course, that there had been no slips in the experiments.

But Abbe Spallanzani thought that he detected such slips in
Needham's experiment. The possibility of such slips might come