Nickel-plated brass window screws usually replaced plain brass ones around the turn of the century 1900. Normally, all the windows in the house were screwed shut, except for the occasional sash, which was made openable thanks to a pair of hinges with a loose angle print. The fitting consists of two parts, a coarse screw that is screwed through the sash and a counterplate that is attached to the window center post.
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