An oriel window is really a style of bay window that does not achieve to the bottom. In its place oriel windows are usually supported by corbels or brackets. Can not open up thoroughly, contrary to double casement windows as there is always the dimensions of one sash about the window.  https://frenchbulldogstatue10987.yomoblog.com/42220803/top-guidelines-of-sash-window-draught-proofing