Notes from the John Martin Rare Book Room March 2013
Aselli was born at Cremona, studied medicine at Pavia receiving degrees in medicine, surgery, and philosophy. He spent his professional career as a surgeon in Milan performing many anatomical and physiological experiments including those that led to his rediscovery of the lymphatic vessels. The lymphatics had been described earlier but no one had been successful in identifying their functional significance. Aselli wrote many unpublished notebooks and papers to record his work on medical subjects including surgery, therapeutics, recurring calculi, anal fistulas, and poisonous drugs. The latter was important because it was the first time drugs had been classified by their clinical effects and toxic actions. While vivisecting a dog to demonstrate the recurrent nerves and diaphragm, he discovered a network of mesenteric vessels that contained a milky white fluid. He had uncovered the mesenteric lymphatic vessels which he called the lacteals. After repeated experimentation, he concluded that they lead into the liver which was believed to be the central organ of the venous system. It remained for Pecquet to correct Aselli’s misconception when he discovered the thoracic duct in 1651. The woodcuts are treated in a very spirited manner and in colored chiaroscuro. The wood blocks are the earliest anatomical illustrations in color printing.