What are these Greek circular wall projections? (round pilasters)

• A. Free-standing columns
• B. Engaged columns
• C. Pilasters
• D. Buttresses

Answer: (B)

These features illustrate a distinction between elements that are part of the wall and those that stand freely. In classical architecture, pilasters are flattened, rectangular projections that run along the wall, echoing a column but staying attached to and embedded in the surface. When a projection is circular in cross-section and appears as a full column that is bound to the wall, it is an engaged column—a half or partial column that is attached to the wall and contributes to the façade’s rhythm without being free-standing. Free-standing columns sit apart from the wall, buttresses push outward to counteract thrust, and pilasters remain flatter and rectangular. So the round wall projections described are engaged columns because they are column-like forms anchored into the wall rather than independent columns.