The two corner domes of the north wing are not oval in shape like those in the
south wing. Instead they are circular in shape. This design change from Alfred
Mullett's plan was done by Thomas Lincoln Casey, the last Supervising Architect
of the Treasury to follow Mullett. Casey made the change to speed up the construction,
minimize material waste, and reduce the construction cost. All this was possible because
stairtreads under a round dome are all the same size rather than individually custom cut
to fit under an oval dome.
The Northwest Corner Dome, date unknown. EOP Preservation Office.
The north corner domes were repainted in their original colors in 1984.
They were once used as a filing center for the War Department.
Northeast Corner Dome, 1985. Walter Smalling, Jr.