partial insight into the nature of disease. The shades of ignorance, however, still gathered thickly over the subjects of pathology and therapeutics, whilst physiology was merely struggling into light.
It is a curious speculation to realize what the state of medical knowledge must have been whilst the circulating system remained still unrevealed. The depth of obscurity in which all the functions of the body during health, and all the morbid changes which constitute disease, must have been then involved, is by us now barely to be conceived. Yet we ought to estimate it fully in order to do justice to the amazing intelligence of those who, gifted with an almost prophetic mind, were able to perceive that, on the explanation of that great mystery, the whole future existence of medicine as a science hung suspended.
One undaunted pioneer on the road to this discovery had been cut off. The fate of poor Vesalius, wrecked and starved to death, always demands a passing word of sympathy. Had he lived, the progress of inquiry would
