Section of a parapet (_) 

This pencil sketch by Karl Ballenberger is a study of architectural details, likely a parapet from a building. The drawing showcases a repeating pattern of arches and geometric shapes, with careful attention paid to the delicate curves and lines. The precise and detailed nature of the drawing suggests the artist's interest in the formal elements of architectural design. This study would have been useful for Ballenberger as he created larger, more complex architectural works.