first he vigorously opposed what he considered to be an attempt to retain the old-fashioned ligatures in preference to his new acupressure; but with his penetrative eye he must have foreseen that should the new practice prevail and short absorbable ligatures be made possible, acupressure would be completely superseded. In the estimation of the writer of the obituary notice of Professor Simpson in the _British Medical Journal_, the greatest of all his works was that undertaken in the subject of Hospitalism. As early as 1847 he had been horrified to read in a report of the work done in the Edinburgh Infirmary, that out of eighteen cases of primary amputation performed during a period of four years only two survived. He faced this fact with the courage of the reformer, and sought far and near for other facts to support the theory which he gradually evolved, that this melancholy failure of surgeons to save their patients' lives was due not so much to the operation or the operator as to the environment of the patient. In later years he himself often shrank, on account of unfortunate experiences, from performing capital operations which he had formerly unhesitatingly undertaken. The unhealthiness of hospitals had long been recognised; and was especially observed at times when they were overcrowded, as happened during war time. When the public had thoroughly grasped the utility of anaesthetics, and recognised that operations could be performed painlessly, there were fewer refusals to submit to the knife; there was a rush to the hospitals, and the surgical wards throughout the length and breadth of the land became crowded with men and women actually longing for operation. Amongst these all the dreaded sequelae of surgical interference, which no power seemed able to check, ravaged with alarming severity. It is to Simpson's credit that he perceived how the introduction of anaesthesia had taxed the hospitals and bewildered the operators, who sought diligently but unsuccessfully in every direction for some means of reducing hospital mortality. He was one of the first to set to work with method to investigate this question of Hospitalism.