The map above is like a time machine. It shows San Francisco's Chinatown in 1885, and it suggests it was a pretty wild place. The color coding depicts several kinds of trouble a person could get into back then: gambling dens are pink, opium dens are yellow, and prostitution is either blue or green depending on the ethnicity of the prostitutes.

The red blocks are joss houses, or Chinese folk temples.

I first heard about this map from David Rumsey, who has a copy of it in his collection (and online, where you can zoom in to see more detail). Rumsey recently invited me and Betsy over to his house to see his maps, and we'll have much more to say about his collection – one of the largest private map stockpiles in the world – in future posts.

My first reaction to this map was: Chinatown was a lot more fun back then. These days it's overrun with tacky souvenir shops and touristy restaurants. It's not my favorite part of town. But then Rumsey told me about the nefarious scheme behind the map.

David Rumsey Map Collection )

It was basically part of a plan by the city supervisors to push Chinese immigrants out of the city.

To get some historical background, I called up Susan Schulten, a historian at the University of Denver, who recently blogged about the Chinatown map herself.

Anti-Chinese sentiment was running high throughout the West in the latter half of the 19th century, Schulten said. Government policies in the mid-1800s encouraged Chinese immigration to help build the transcontinental railroad. Then, around the time the western end of the railroad was wrapping up, a huge financial crisis hit: the Panic of 1873. Suddenly there were a lot fewer jobs.

The notion that the immigrants were taking jobs away from Americans started to take root and grow. "The Chinese in particular were seen as a menace because they would work longer and harder for lower wages," Schulten said. This led to resentment and racist policies intended to stem the perceived threat. (Good thing we've put all that behind us...)

To illustrate what was going on at that time, Schulten emailed me a list of discriminatory laws passed in the 1870s. Here are just a few:

Sidewalk Ordinance of 1870: prohibits people who use poles to carry merchandise from walking on the sidewalk (non-Chinese used wagons and carts).

Cubic Air Ordinance of 1871: requires all adults to have more than 500 cubic feet of living space (San Francisco's Chinatown was severely overcrowded, and hundreds of Chinese were jailed for breaking this ordinance).

Laundry Ordinances of 1873 and 1876: mandates high licensing fees from anyone who carried laundry without a horse-drawn wagon

Then, finally, came the surprisingly bluntly named federal Chinese Exclusion Act of 1882, which banned Chinese immigration. Chinese immigration to the U.S. dropped from 40,000 in 1881 to 10 – that's right, ten – in 1887.

Meanwhile, back in San Francisco, the city's board of supervisors sent a special committee to Chinatown to investigate conditions there. They produced the map above and a report that accompanied it. "They were trying to show how depraved the culture was in Chinatown," Rumsey said. "It's pretty frightening to read today because it's so anti-Asian."

Indeed it is. Here is a bit from the introduction:

Your Committee were at that time impressed with the fact that the general aspect of the streets and habitations was filthy in the extreme, and so long as they remained in that condition, so long would they stand as a constant menace to the welfare of society as a slumbering pest, likely to generate and spread disease should the city be visited by an epidemic in any virulent form. Your Committee are still of the opinion that it constitutes a continued source of danger of this character, and probably always will, so long as it is inhabited by people of the Mongolian race.

It goes on (and on, and on) about the filth and supposed moral turpitude in that part of town, and concludes by arguing for more regulation both at the municipal and federal level. "We have permitted the Chinese to become our masters, instead of asserting and maintaining the mastery ourselves," the committee writes towards the end.

In his 2001 book Contagious Divides, historian Nayan Shah argues that the map and the allegedly scientific investigation that produced it helped define Chinatown as a civic problem and emboldened the city's newly created Board of Health to intervene in the lives of its residents with surveillance, inspections, and especially vigorous enforcement of sanitary laws.

It's interesting to contrast the Chinatown map with other maps from roughly the same time. Below, there's a closeup of the Chinatown map and below that is the corresponding section of a 1905 Sanborn fire insurance map from Rumsey's collection (it's a rare thing – it survived the 1906 earthquake and fire and is a little worse for the wear). But while the color scheme of the Chinatown map was chosen to highlight vice, the Sanborn map is more neutral. Even so, if you look closely at the Sanborn map you can see some evidence of vice. It's just a little more subtle, referring to "club gambling rooms" and "female boarding."

The Chinatown map was made at an interesting time in the history of cartography, Schulten says. The mid-19th century saw the rise of thematic mapping. Previously, cartographers made reference maps to illustrate the topography of a region, and perhaps its roads and political boundaries and other features helpful for navigation. Now they began making maps that incorporated many other types of information about a place, about its climate and its people, for example (this is the focus of Schulten's fascinating book Mapping the Nation, which came out earlier this year).

And given the political climate of the time, many of these maps dealt with things like race, immigration, and disease. In 1874 the U.S. Census Bureau produced a landmark statistical atlas based on its data from the 1870 census. The atlas includes maps on the proportion of foreign born to native populations, as well as maps on disease and illiteracy, encouraging readers to look for relationships between immigration and social ills.

The goal was to promote better governance and the welfare of society, Schulten says. But 19th century ideas about social welfare don't always mesh with modern values. And as the San Francisco Chinatown map shows, maps can be made to promote bad public policy as well as good.

David Rumsey Map Collection )