Tuesday, April 2nd, 2013 11:23 PM   Cannonade tread across the roofs of Southside, looking down on the streets below. He was looking for some sign that might lead him to the answer to the latest mystery in a city that never seemed to run out of them. Specifically, he was looking for an anachronism.    He'd first learned about the issue at work, the week before. Harry, one of the long-time guys, had been talking about his brother. The guy had been working at a construction company that had g