Gas lighting was known for making a mess. Factory owners didn’t know what to do with coal tar, the sticky, toxic byproduct of coal gas production. They tried dumping the byproduct into rivers, but it ended up killing fish.
After Thomas Edison’s creation of the lightbulb in the 1880s, the technology gradually fell out of use in the 20th century, but gasworks plants left a legacy in the landscape. In Seattle, for example, the iconic Gas Works Park along Lake Union was once home to a major coal gasification plant that opened in 1906, filling the area with smelly, bubbling char for 50 years until it closed.