intercourse that carried the seeds of infection. The venereal disease
epidemics provided further evidence that contagium animata were real.
Jacob Henle, writing in his classic 1840 essay, “On Miasmata and
Contagia,” conducted a series of Einsteinian “thought experiments,” using
only reasoning to ponder epidemics and pandemics.^19 Because microscopy
was still limited, he used his imagination to elucidate the foundational
underpinnings of germ theory (later inspiring his star pupil Robert Koch,
in Göttingen). He considered cow-pox, where “an atom of pox poison can
produce a rash over the entire body.”^20 Predating Pasteur, Henle
considered fermentation of wine, concluding that it was the
“decomposition of an organic fluid by vegetable bodies.”^21 In both these
instances, the multiplication or amplification of byproducts suggested
living organic beings. It simply did not make sense that an elemental
poison or toxic gas could rip through a community on a more than additive
(an exponential) basis. Amplification was occurring, and something living
had to be multiplying itself within people’s bodies.
Lister was becoming increasingly convinced that a surgical wound
oozing with pus was not simply inflamed and “healing,” but was instead
putrefying, infected, and necrotic. His investigations on wild rabbits, dead
cows, and oxen continued, as well as experiments and microscopic
evaluations of inflamed frog feet, with Agnes at his side, in their kitchen.
Had Lister been a lone genius with a magical microscope, he still needed a
gentle nudge to help him take an important conceptual leap. Prior to the
invention of the printing press and the formation of peer-reviewed
scientific journals (e.g., Philosophical Transactions of the Royal Society),
isolated savants could never “see further,” but with the revolution of
information sharing, geniuses could connect. In Glasgow, in 1865, Lister’s
colleague in the chemistry department recommended that he read the
publications of Louis Pasteur regarding fermentation of beer and wine in
the Comptes Rendus de l’Académie des Sciences. Lister, the English
surgeon practicing in Scotland, sat down to read the Parisian chemist’s
French publications, an act which would change surgery forever.