A Question of Piping

Q. Do you know the purpose, if any, of the copper pipes bracing (or embracing) the columns on the uptown side of the Wall Street subway platform?

A. It’s not plumbing; it’s art.

The nine hand-forged bronze seat rests at the Wall Street station on the 4 and 5 lines do indeed resemble copper pipes. But they are a sculptural installation called “Lariat Tapers,” a 2011 work by James Garvey.

Deirdre Parker, a spokeswoman for New York City Transit, says the tapers swirl in a clockwise direction around the columns to depict the motion of trains swooping into the station. They can be compared with Mr. Garvey’s similar 1997 artwork “Lariat Seat Loops,” at the 33rd Street station on the No. 6 line.

Purple Snow

Q. We all know about yellow snow, but what about purple? I spotted a strange color in the virgin snow in my backyard. It was a bright purple-magenta color in spots under a barren tree. Up the block, I spotted additional similar stains in the snow out on the sidewalk. What’s up?