In an alternate universe, Boston's Dorchester neighborhood would be the Big City, as it was founded several months before the more famous Beantown. Established in 1630, the population grew exponentially with the ease of transportation via the Old Colony Railroad revolutionized Dorchester in the period between 1850 and the Civil War. Primarily still a rural town with a population of about 12,000 by 1870, the town was annexed to...