In pondering over what he had learned about collateral circulation and the time required for it to become fully established, Hunter conceived the idea that if the blood-supply was cut off from above the aneurism, thus temporarily preventing the ceaseless pulsations from the heart, this blood would coagulate and form a clot before the collateral circulation could become established or could affect it. The patient upon whom he performed his now celebrated operation was afflicted with a popliteal aneurism--that is, the aneurism was located on the large popliteal artery just behind the knee-joint. Hunter, therefore, tied off the femoral, or main supplying artery in the thigh, a little distance above the aneurism. The operation was entirely successful, and in six weeks' time the patient was able to leave the hospital, and with two sound limbs. Naturally the simplicity and success of this operation aroused the attention of Europe, and, alone, would have made the name of Hunter immortal in the annals of surgery. The operation has ever since been called the "Hunterian" operation for aneurism, but there is reason to believe that Dominique Anel (born about 1679) performed a somewhat similar operation several years earlier. It is probable, however, that Hunter had never heard of this work of Anel, and that his operation was the outcome of his own independent reasoning from the facts he had learned about collateral circulation. Furthermore, Hunter's mode of operation was a much better one than Anel's, and, while Anel's must claim priority, the credit of making it widely known will always be Hunter's. The great services of Hunter were recognized both at home and abroad, and honors and positions of honor and responsibility were given him. In 1776 he was appointed surgeon-extraordinary to the king; in 1783 he was elected a member of the Royal Society of Medicine and of the Royal Academy of Surgery at Paris; in 1786 he became deputy surgeon-general of the army; and in 1790 he was appointed surgeon-general and inspector-general of hospitals. All these positions he filled with credit, and he was actively engaged in his tireless pursuit of knowledge and in discharging his many duties when in October, 1793, he was stricken while addressing some colleagues, and fell dead in the arms of a fellow-physician. LAZZARO SPALLANZANI