“Compass & Rule: Architecture as Mathematical Practice in England, 1500-1750” is on view through May 30 at the Yale Center for British Art, 1080 Chapel Street, New Haven; (203) 432-2800.

Description This leg for a drawing compass has a brass top, which is jointed, and German silver pen points with an adjusting screw. Loosening the screw increases the width of the pen line to be drawn.

advertisement 11-24-2014 DESIGN A Compass That Can Draw Digital Files The invention can also “copy and paste” from real life.