During the 19th century, it was widely believed that bad smells carried diseases. In the 1870s, the New York City Metropolitan Board of Health created the below "stench map" to point out where malodorous industries—then called "offensive trades"—were located in the city.
"Trying to show smells, which are not concrete—they're invisible, they're ephemeral, they're always changing—is just a really fascinating cultural project," says Melanie Kiechle, a historian at Virginia Tech University who has written about urban odors for the Journal of Urban History.
Other urban problems, such as crime and cholera, had already been mapped by the mid-19th century, but bad smells were a less tangible city experience. Health officials at the time actually sniffed the air to document where the smells were coming from and where they were blowing toward. But the Metropolitan Board of Health map does more than identify the source of these odors; it also reveals how some bad-smelling industries ended up in Brooklyn, ultimately contributing to the industrial landscape there.
The map shows several smelly factories in Brooklyn that relocated from Manhattan in the late 1860s and 1870s partly because of ordinances passed by the Metropolitan Board of Health that restricted the presence of "offensive trades" on the island. In Brooklyn, smells weren't regulated as strictly by the 1870-born Brooklyn Board of Health, says Kiechle. But even from outside Manhattan, these industries caused problems: winds carried their stink back toward Manhattan, generating friction between the health bureaus of the two regions.
By the end of the 19th century, a broader acceptance of germ theory had weakened the belief that odors caused diseases, and the technology to restrain odors had improved. Both of these developments meant that bad odors weren't quite the nuisance they had been before. But by this time, they had already caused an outward shift of industries to Brooklyn, helping build its reputation as an industrial hub in the 20th century.
Today, Brooklyn's industrial past is still visible in some neighborhoods. Industrial operations that produce offensive odors still seem to be relegated to some of the same areas as those shown in the "stench map," says Kiechle. The Newtown Creek area on the border of Brooklyn and Queens is still the site of a sewage treatment plant, for example.
What's also interesting is that Newtown Creek and the Gowanus Canal (both next to the smelly industries in the map at the top) have been designated superfund sites by the Environmental Protection Agency. So today, some of the spots the "stench map" highlights are hazardous to health—just not because of their smells.