A similarly variegated effect in red and white is produced by building the arches of windows and doors with alternating voussoirs in brick and marble.
The arches, round or more often pointed in form, were decorated with moulded terra-cotta enrichments, and often with alternating voussoirs of marble.
The arch ring can be treated as a blockwork structure composed of rigid voussoirs.
The voussoirs of the centre arch (all of granite) are 4 ft.
could be ascertained, the line of pressure lies within the middle half of the depth of the voussoirs.