Mr. Frederick Treves (_The Lancet_, January 21, 1888). In the neck, pressure upon the carotid artery, in hæmorrhages from the branches of that vessel, cannot be applied in the ordinary way with success, nor could it be maintained for a sufficient length of time, if the pressure succeeded in arresting the hæmorrhage, to be of service. Treves proposes, however, to occlude the vessel temporarily by throwing a broad piece of catgut around it, tying it in a loose loop, and then making traction upon the same. The circulation through the vessel is at once arrested, but can be at once restored upon relaxing the tension upon the loop. He relates four cases in which the method proved successful, so far as the arrest of the bleeding was concerned. One of the patients succumbed to the great loss of blood sustained prior to the application of the ligature, although the other carotid had been previously tied. In the first case the loop remained _in situ_ for four days. The second case was the fatal one. In the third and fourth cases the loop was removed on the seventh day. The method is based upon the fact that temporary arrest of the circulation in certain cases of hæmorrhage from the limbs, where ordinary means may be employed to exercise pressure, are quite sufficient, not only for the purposes of a temporary expedient, but also seems as a curative measure. This temporary modification of the blood current may be all that is required in many instances. Just how long the blood current may need to be checked, must be carefully studied in each individual case. The thought occurs to us, however, that some risk may be run of setting up an ulcerative action in the vessel walls by the prolonged application of a loose ligature, upon which must be exercised an intermittent pressure, by the pulsation of the vessel itself. ARTIFICIAL AID IN THE FORMATION OF CALLUS.