What were some of Andreas veslaius achievements?

He corrected Galen's mistakes of the heart, circulation of blood and of the human jaw bone. Vesalius corrected Galen's mistakes and even though he had to prove his ideas all of this was possible because he was able to dissect bodies.

He corrected that the human jaw bone has only two bones and not five (five in animals). Furthermore, he showed through dissection that the circulation of blood flowed and that no new blood was created. It was that the heart would act as a pump and pump the blood around the body not the liver!!