Part of a set of components which may be assembled in all sorts of ways to create a wide variety of stone buildings from simple farmhouses through posher urban terraces to more complex villas, hotels and even palatial manors without putting undue strain on resources because the same basic units can used again and again in various combinations.
Corbie (or 'Craw/Crow Step') gables are a characteristic Scottish architectural feature, and this unit is set at the right height to 'slide' straight onto the Wing Units to convert them to a Corbie profile. It is shown alone on the right and on each of the wings of the semi-detached houses which dominate the left of the picture.