Not ever in my wildest dreams could I have had access to this place. But the architect restoring part of the Capitol is a friend of mine, so... Besides the two friends doing the drawings had been before to take the lantern's info.
The circular stained glass oculus is not that large in diameter. I suppose the frame is to hold the strengthen the steel ring and also as support for the lamps.
It's been sort of a wild but interesting ride. All the haste and time consumed, like an intensive course. I've learned about so many historical things... Pirate attacks, tunnels, demolished chapels, walls, bastions... Things like how sometimes all the structures close to the shore were painted white at times to scare off pirates at night (making them believe the city was larger than it was), why churches were usually located in high places (to be used also as watch posts), why powder magazines had what we all along thought were chimneys (nobody really knew why; the answer: they were not chimneys but towers to place lightning rods - as plain as that. It was thought that they were made to look like chimneys so that attacking enemies would thought they were mere kitchens), etc.