Mr. Gallagher heads out on foot or on his bike with a backpack full of chalk, looking for shadows to trace. When he tells you that “everything is fair game,” he means it. He has traced everything from hydrants to whole city blocks….
On a recent evening, a man named Steve stopped to watch Mr. Gallagher work, despite the cold. “A million times I walked by a street sign, how come I never thought to do something like that with a piece of chalk?” Steve asks. Mr. Gallagher smiles when he hears this, watching a new fan walk off down the street.
“It’s very touching,” he says sincerely. “People tell me ‘you make me smile’ or ‘you make me stop and think,’ and that’s cool. I make a difference in people’s lives. It inspires me to create more.”

I stumbled across Ellis’ shadow outlines in Park Slope while walking with a friend a few months ago. The very bright colors of the chalk highlights the contours of shadows you probably wouldn’t have noticed otherwise. The effect is pretty mesmerizing: the shadows glow, and the sidewalk gains this weird illusion of depth. Just about everybody on the block was stopping to look, take photos, and talk about the tracings..
Jake points out on Gothamist that sidewalk chalking is not necessarily illegal, and Ellis states in the article that he goes chalking any time he feels like it, without fear of harassment or arrest. It’s a reminder that art doesn’t have to be confrontational or complicated to have an effect.