by Rehne Burge, C.A. Have you ever wondered where it all started? How did we discover the circulatory system and how it functions? And what does that have to do with essential oils? Let's take a sneak peek. Anatomy has been recorded as the oldest known of medical science. And through the history of anatomy, there have been many theories, a great deal mostly inaccurate or simply wrong, explaining anatomy and physiology. These theories, some dreamed up, were by physicians, surg