| Major Contributions | Person | Life |
|---|
| Claimed illness is not caused by God, invented the Theory of the four humours, made doctors take an oath of secrecy | |
| Advanced the theory of the four humours, Dissected animals to discover more about anatomy and wrote many books which were used for hundreds of years after him | |
| Wrote the first medical encyclopedia, documenting all known medical knowledge of the time | |
| Replaced cauterisation of arteries with ligatures; used ointment for wounds rather than boiling oil | |
| Human dissection; disproved many of the Roman ideas about anatomy | |
| Proved blood was circulated, not used like fuel; discovered the heart was a pump | |
| Improved the microscope- first person to observe germs | |
| Discovered that giving people cowpox prevents them getting smallpox; made the worlds first vaccination for smallpox | |
| Made doctors wash their hands before treating women in childbirth | |
| Laid down the foundations of professional nursing; improved conditions in hospitals and for injured soldiers in the Crimean War | |
| Discovered that microbes (germs) cause disease | |
| Pioneered the use of antiseptics in surgery and promoted sterile surgery | |
| Discovered that certain microbes cause certain diseases, created a method isolate the bacteria responsible for diseases | |
| Discovered x-rays | |
| Discovered the first antibiotic- penicillin | |
| Improved the extraction and mass production of penicillin | |
| Carried out the first successful human-human heart transplant | |
| Lead the Human Genome Project and made many discoveries about genetic diseases | |
U.S. Presidents 
Famous Wars 
Original 13 Colonies
