Screens composed of various materials, and fixed in window frames, either to exclude a too strong light, or to screen the interior of an apartment from the observation of persons on the outside, without obstructing the view of those within. The contrivances for these purposes are numerous, and so well known as to require no particular description; we shall, therefore, only notice a blind for circular headed windows, as these windows are common in modern churches, chapels, and public building, and the heads have hitherto been either left entirely without blinds, or the blinds have been awkwardly contrived, and unsightly in their appearance. Fig. 1 is an elevation of the arch of a window; a a a metal tube bent so as to fit the head of the window, and serving as a circular curtain rod; this rod is open all along the upper edge, as shown in the section Fig. 2; the ends fit into holes at b and c, made through the window bar at d; at b, a pulley is fixed, corresponding with the holes and bore of the bent tube a; an endless band e e e Figs. 1 and 2 enters the tube a by the end c, goes out at the other end, passes under the pulley b, then crosses the window below the bar d, passes over the pulley c, and then over a spring catch, or rack pulley, not shown in the drawing.
In order to make the blind, a piece of cloth is taken a little wider than the height of the arch, and rather longer than its circumference, and is folded like a fan; a nail is then passed at the bottom through all the folds into the middle of the window bar at d, forming a centre to the semicircular tube a a; holes are made at the other end in the folds, which allow the blind to slide along the tube; the bottom fold is tacked to the window bar near the end b; two pieces of tape connect the upper fold with the endless band by passing through the split tube as shown. The blind is drawn over the window, or withdrawn from it, according as one side or other of the endless band is pulled, as in the common roller blind. The inventor of this excellent contrivance, Mr. H. Goode, of Ryde, Isle of Wight, was presented by the Society of Arts with the Silver Vulcan Medal.