| A large oculus brings a cylinder of light down into the main library, bathing the interior in a softly luminous glow. |
| The light entering through the oculus at the top floods the space with hypnotic patterns of light and shadow. |
| The sun streams in through the open oculus, tracing a circular disk across the walls and floor, creating a walk-in solar observatory. |
| The major interior space, the Potomac rotunda, balloons under a domed ceiling with an oculus, reaching a height of 120 feet. |
| At the centre of the dome is an oculus, a circular hole, which is the only source of light. |
| This hidden Eden continues to baffle geologists with its oculus of volcanic stone. |
