The method of operating the wings or ventilators of hot-air registers, has heretoiore been attended with some inconveniences that appear to be obviated by a very simple contrivance invented by S. T. Munson, of New York City. The nature ot his invention consists in having the wings of the register attached at one end to a slide oy means of bent arms, the outer ends of which fit loosely in apertures in the Sides, said arms being secured to the wings at points some distance from the centres. The slide is operated by means of a lever having a slot in it, through whichslota small projection from the slide passes. By operating the lever, motion is given the slide, and the wings are operated or cleared according to the direction in which the lever is moved. An impetus is given the lever as it is moved by means of a spring placed at its lower end. The spring also prevents the casual movement of the lever. Measures are taken to secure a patent.