The Ebers Papyrus, also known as Papyrus Ebers, is an Egyptian medical papyrus of herbal knowledge dating to circa 1550 BC. Among the oldest and most important medical papyri of ancient Egypt, it was purchased at Luxor in the winter of 1873–74 by Georg Ebers. It is currently kept at the library of the University of Leipzig, in Germany. The papyrus was written in about 1500 BC, but it is believed to have been copied from earlier texts. The Ebers Papyrus is a 110-page scroll, which is about 20 meters long. Along with the Kahun Gynaecological Papyrus (c. 1800 BC), the Edwin Smith Papyrus (c. 1600 BC), the Hearst papyrus (c. 1600 BC), the Brugsch Papyrus (c. 1300 BC), the London Medical Papyrus (c. 1300 BC), the Ebers Papyrus is among the oldest preserved medical documents. The Brugsch and the London Medical papyri share some of the same information as the Ebers Papyrus. Another document, the Carlsberg Papyrus, is identical to the Ebers Papyrus, though the provenance of the former is unknown. The Ebers Papyrus is written in hieratic Egyptian writing and represents the most extensive and best-preserved record of ancient Egyptian medicine known. The scroll contains some 700 magical formulas and folk remedies. It contains many incantations meant to turn away disease-causing demons and there is also evidence of a long tradition of empiricism.The papyrus contains a “treatise on the heart”. It notes that the heart is the center of the blood supply, with vessels attached for every member of the body. The Egyptians seem to have known little about the kidneys and made the heart the meeting point of a number of vessels which carried all the fluids of the body—blood, tears, urine and semen. Mental disorders are detailed in a chapter of the papyrus called the Book of Hearts. Disorders such as depression and dementia are covered. The descriptions of these disorders suggest that Egyptians conceived of mental and physical diseases in much the same way. The papyrus contains chapters on contraception, diagnosis of pregnancy and other gynecological matters, intestinal disease and parasites, eye and skin problems, dentistry and the surgical treatment of abscesses and tumors, bone-setting and burns. The “channel theory” was prevalent at the time of writing of the Ebers papyrus; it suggested that unimpeded flow of bodily fluids is a prerequisite for good health. It may be a considered a precursor of ancient Greek humoral pathology and the subsequently established theory of the four humors, providing a historical connection between Ancient Egypt, ancient Greece, and medieval medicine.