From January to May 1991 I was in Siena, Italy as an apprentice to Dr. Kim Veltman. My work involved creating three dimensional animations of significant drawings from the history of perspective. On weekends we took all kinds of trips around central Italy. I was incredibly lucky to be touring with the world expert on perspective. He was researching the medieval precursors to perspective and we found ourselves spending a lot of time looking at paintings of the lives of various saints in monasteries, especially Franciscan and Dominican.
We visited the Sistine Chapel at St. Peter's Basilica, but what was more memorable for me was our time waiting in the antechamber known as the Map Room. Here are a couple images to give a sense of the space:
Kim noticed there are some loose correlations between saints depicted on the ceiling and the maps of Italy on the walls. If we hadn't been immersed in details of the lives of various saints he might not have noticed the connections. Now consider the punchline from the demo of Photosynth: by virtue of spatial relationships between photographs, each user's "own photos are getting tagged with metadata that somebody else entered. If somebody bothered to tag all these saints to say who they all are then my photo of Notre Dame cathedral actually gets enriched with all that data and I can use it as an entry point to dive into that space. ... And of course a byproduct of all of that is immensely rich virtual models of every interesting part of the Earth."
Ever since I visited the Map Room I've wished I could go back over the various connections between the saints and the historical maps of Italy where those saints lived and worked. I had imagined a virtual reality application where one could click on links in the ceiling images and see highlights appear on the corresponding maps. I imagined following several different trails from there. In one I just explored a stream of images of historical maps of Italy to watch how geographic technology improved over time. In another I could explore other areas on the maps where events in that saint's life took place. In another trail I dipped back into my Dream Encyclopedia and watched how the borders of the Roman Empire changed over time.
Between wikipedia, flickr, photosynth, and sea dragon my dream encyclopedia may yet come to pass. It's an exciting time to be alive!