Sir Frederick William Hewitt (1857-1916) wrote one of the earliest comprehensive textbooks on anaesthesia, and designed several pieces of anaesthetic equipment. In 1901, he described his wide-bore ether inhaler, a modification of the Clover Ether Inhaler. Unlike the Clover, it can be refilled with ether while still in use, and the mask is screwed into place so that it "cannot be unexpectedly detached." This version is a modified Hewitt's Inhaler which has a narrower 'ways' than the original Hewitt's, and no water compartment. Additionally, one side of the bowl is made of glass which enabled the person administering anaesthesia to see the level remaining in the bowl. Bowl shaped inhaler with a glass bowl base and metal dome top with a connector which appears to be for a rebreather bag. There is a metal switch at the base of the glass bowl to alter or regulate the flow.Stamped into central tube: COXETER LONDON Stamped into side of metal dome: 6460hewitt, wide-bore, clover, ether, anaesthesia, anesthesiology, anaesthesiology