Train writing. Call it art, call it graffiti - these messages on a bottle crisscross North America by the thousands, a mobile menagerie of insults, strange beings, personal signatures, poems, political piths, and social commentary. They are America’s public folk art on wheels, a self-renewing gallery set loose to roam the rails. They are counter-culture statements, spoken by spray can in secret, a quiet defiance. Many of the rail yard crews collect their favorites on cell phones. Rail managers often hang them in their offices or homes. I started photographing train graffiti several years ago after watching Style Wars, a film documenting the New York subway writers and hip hop scene of the 1980s. As they roll past I get two seconds - perhaps three - to shoot them. Seldom will I see them again. Each one is destined to be buffed by the sandblaster or paint gun. For me, they are a breath of fresh air brightening a culture where - for most - art is an afterthought, and public art has no standing.