LONDON, ENGLAND—While constructing a section of Crossrail, a 73-mile high-speed railway set to connect far-flung parts of London in 2018, workers stumbled upon a pit in the Charterhouse Square section of the city that contains several burials which scientists believe are tied to the early years of the Black Death. The skeletons, 13 so far, were found along with ceramics that date to the middle 1300s, when the plague was arriving at its peak. The bodies, which are arranged in two neat rows within the 18-foot shaft, could help scientists learn about the lifestyle of mideval Londoners, as well as offering an opportunity to learn about the spread of the pandemic.