This sheet is a study for an unrealized painting commissioned by Charles Marcotte, Rome’s inspector general of waterways and forests and a great friend of Ingres’s. It depicts Santa Maria Maggiore’s Borghese (Pauline) Chapel, viewed from the church’s nave, during a devotional rite called the Quarantore that involves forty hours of continuous prayer. Although figures are scattered throughout the composition, the artist imbued the scene with a sense of calm and stillness, emphasizing architectural symmetry and the interplay of light and shadow.