ADDITIONAL NOTES:The Pantheon: Circa 125 A.D., "the best-preserved example of monumental Roman architecture" is filled with people looking up in awe at its engineering marvel of a ceiling:
The interior of the roof was probably intended to symbolize the arched vault of the heavens. The Great Eye at the dome's apex is the source of all light and is symbolic of the sun.... The oculus also serves as a cooling and ventilation method. As wind passes over the dome of the Pantheon, it is accelerated and creates a negative pressure zone called the Venturi effect. This pulls air out of the oculus at the top of the dome, drawing more air in from the portico entrance.