The object of this device is to produce a hinge for doors, window shutters and blinds, and chests, trunks, and boxes that will set door, blind, or lid, at any angle desired, and hold it in that position. It is an ordinary butt hinge, with single joint, having cast on one of the leaves, A,a semicircular flange, B, notched on its edge to receive the pivoted latch, C, that is pivoted to the other leaf, D. On this leaf is cast a snug, E, that receives and holds the end of the latch, C, when down. The opposite leaf, A, has recesses for receiving the snug, E, and latch, C, when the leaves are closed. In operation, the door, or other valve, whether door, blind, shutter, or chest lid, is opened to the extent desired, and held in any position required by the catching of the latch, C, into one of the notches of the flange, B. It is evident that the door will be held firmly in this position. When it is not required that any stop should be put to the movement of the door, the latch, C, is turned up, its free end resting on the flange, and the door may be swung as any other which is furnished with ordinary hinges. Of course there is a slot cast in the leaf, D, to permit the partial rotation of the semicircular flange, B. Adaptations of this device can be readily made for doors, swinging windows, blinds, inside or out, trunks, chests, boxes, etc. From an examination of the model and the hinge (large size), we are inclined to consider the device a really valuable one, and hinges of this form specially adapted to all the purposes for which they are intended. Patented Jan. 12, 1869, by M. Umstadter, who may be addressed at Norfolk, Va. Perpetual Motion. A correspondent, writing from Ohio, wishes us to use our influence to induce some learned society or wealthy devotee of science to offer a premium for the invention of a perpetual motion. This done, he thinks the invention will be forthcoming ere the end of the year. He speaks mysteriously of a perpetual motion that is almost, but not quite,rbady tb commence its endless labors. Now we have known something less than a thousand just such machines, but they never got quite ready. Under these circumstances, J. W. will please excuse us. We would rather not recommend any societies or devotees to offer any prizes. There is so much immortal genius lying around loose, that such a stimulant might be dangerous.