Workers digging up Battery Park for a 21st-century subway station keep bumping into the 18th century at every turn. For the second time in a few months, workers have uncovered a stone wall that archaeologists believe has stood near the southern tip of Manhattan since New York was a British colony. Like the one found in November, this wall stands in the way of the Metropolitan Transportation Authority's plan to replace the South Ferry station, where the No. 1 train turns around to head back uptown. City officials said they did not yet have a clear idea of when the...