It's in the Video Projector room

You have to be watching the first (leftmost) video to see it. The one with James Burke talking and occasionally showing pictures.

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This solution combines one of those odd things with the content of an actual video.

Start the first video and watch it through the door, rather than the window.

There will be a point where James Burke holds up a book containing a picture with most of a green, "spotted" circle. That circle will line up with the green "spotted" line that goes around the doorway window.

Trace it quickly, and be ready to try again.

(You can save time by fast forwarding and rewinding through the video using the panel where you first drew the path to start the video.)

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This takes some timing.

This one is underground.

You might have noticed some oddly shaped or colored things when you were in there watching videos.

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