Career
He is said to have been personal physician to Pope Innocentius X and Pope Alexander VII. Zacchias was also legal adviser to the Rota Romana, the highest Papal court of appeals, and head of the medical system in the Papal States. His most well known book, (1621-1651) established legal medicine as a topic of study. Zacchias was at the cutting edge of medical pursuit in his time, arguing that poison, infection, and disease were all transmittable through smell:
"We have a thousand and one examples of living beings that have been infected by olfaction alone.
We see many people every day who fall into a serious or very serious state because of good or bad odors."
Zacchias work also contains superstitious views on magic, witches, and demons which were widely held at the time.
He is known to have argued that minors make proper test subjects to be put to torture. Despite these consequences, Zacchias is seen to have radically progressed the works of jurisprudence in medicine of his time.
Is divided into three sections. The first section contains decisions of the Rota Romana during his time serving on lieutenant
The other two sections cover questions of human physiology.
In it he examines problems such as the formation of hermaphrodites, and the animation of the foetus and Superfoetation.