Transfer methods

Many of Sargent’s preparatory drawings for the murals have grid lines over their surfaces. The grids, scaled large on the blank canvas, enabled him to transfer a composition precisely from a small paper sketch to the final canvas while maintaining proportions and perspective. Sargent used two types of transfer grids: rectangular grids, formed by vertical and horizontal lines, as seen on this preparatory drawing for Synagogue, and semicircular grids, formed by consecutive arches intersected by rays, as on this preparatory drawing for Messianic Era.
The Triumph of Religion