Despite the opportunities offered by embalming, the Egyptians made relatively poor progress in the study of the human body. They thought that the blood-vessels carried air, water, and excretory fluids, and they believed the heart and bowels to be the seat of the mind; perhaps if we knew what they meant by these terms we should find them not so divergent from our own ephemeral certainties. They described with general accuracy the larger bones and viscera, and recognized the function of the heart as the driving power of the organism and the center of the circulatory system: “its vessels,†says the Ebers Papyrus,176 “lead to all the members; whether the doctor lays his finger on the forehead, on the back of the head, on the hands, . . . or on the feet, everywhere he meets with the heart.†From this to Leonardo and Harvey was but a step—which took three thousand years.