Spinal veins. Historical illustration of the veins of the spine. The spine runs from the brain (top) to the sacrum (triangular, bottom). The 33 bones (vertebrae) of the spine have been sectioned to reveal the contents of the vertebral canal. This is a protective space inside the spine that contains the spinal cord and veins (blue) that drain deoxygenated blood from the spine. At left, these have been removed to show a further set of veins. A lateral section (upper centre) and a transverse section (lower centre) of a vertebra are shown. Colour lithograph by Fairland from The Vessels of the Human Body, 1837. Based on drawings by J. Swandale.