In Manchester and surrounding factory towns, Engels observed, the “pall of smoke” hung in the air and coated buildings, while tannery buildings, dye works, bone mills, and gas works discharged “filth, both liquid and solid” into the River Irk and “belch[ed] forth black smoke from their chimneys.” Workers suffered from typhus and cholera, struggled to breathe properly, and died much younger than they ought. Those living in the poorest parts of town were twice as likely to die as those in wealthy ones. In Engels’s view, this constituted “social murder”: “If society places hundreds of workers in such a position that they inevitably come to premature and unnatural ends,” he argued, “their death is as violent as if they had been stabbed or shot.” The problem, however, was that this kind of violence was rarely recognized as such. “Everyone is responsible and yet no one is responsible,” Engels wrote, “because it appears as if the victim has died from natural causes.” For Engels, the “disguised, malicious” nature of social murder required all the more vigilance in identifying its culprit—and the vehemence with which he condemned it was a way of bringing it to light.