"San Marco Flow" layers all the actions of people and pigeons on Piazza San Marco in Venice into a pair of evolving images representing two views of the recent history of activities there. The images are, in effect, lit by animate presence; things that are not moving are invisible. Walking pigeons leave worm-like traces. Gathered people abstract themselves through their shifting motions. Tour groups flow across the image like a river. The left side accumulates the activities into a very long exposure image that develops visibly over the course of several minutes. This image has layer upon layer of traces building into a rich and complex image that is very painterly and find many resonances with the history of Art and the history of the piazza itself. In the projection on the right, the past fades more quickly resulting in a gently dynamic flow. The evolving images are presented as two video projections mirrored at their point of meeting. They are different readings of the same unfolding source material providing a kind of stereoscopy into the dimension of time. They present a record of the temporary social architecture that is shaped by the permanent physical architecture of the piazza.