this piece that we are looking at now is by bella felledman, an east bay artist who is in her 80s and still incredibly dynamic and productive. all of her life she's been interested in machines. she said she doesn't particularly like machines, but her art is all about them. >> the use the term public art. what is public art as opposed to something else? >> there is this phenomenon post world war ii in many cities across the united states, and san francisco has been one of the leaders, whenever the city builds an airport, a fire station, a school, library, the city is committed to 2% of the budget for that construction. it has to be permanent art for the building. it has to be integrated. it can't be just stuck on. so it's created a field, an opportunity, for contemporary living artists to have permanent outdoor pieces and the amount of money that goes to the art is quite substantial. >> i wanted to jump in. i think to renny's great vision of the show, many artists came from somewhere else. you can look at the machine as a way of making sense of life, a way of being an immigrant in a ne