The history of germ theory in the College collections

Marcus Terentius Varro (116–27 bc)
De re rustica
Venice, 1514

The idea that certain diseases were caused by minute living creatures invisible to the human eye goes back more than 2,000 years. The Roman scholar Marcus Varro was director of the imperial library at
Rome and the author of the above work on agriculture. Varro warned against locating homesteads in the proximity of swamps ‘because there are bred certain minute creatures which cannot be seen by the eyes,