Buckle up! The Weeds Time Machine is back. Today, Dylan Matthews, Dara Lind, and special guest Maureen Cropper, economist and professor at the University of Maryland, travel back in time to the 1970s to discuss one of the most important pieces of environmental legislation of the 20th century: the Clean Air Act.  References: White paper: Looking Back at 50 Years of the Clean Air Act  Hosts: Dylan Matthews (@dylanmatt), senior correspondent, Vox Dara Lind (@dlind), Weeds co-host, Vox Credits: Sofi LaLonde, producer and engineer Libby Nelson, editorial adviser Amber Hall, deputy editorial director of talk podcasts Sign up for The Weeds newsletter each Friday: vox.com/weedsletter  Want to support The Weeds? Please consider making a donation to Vox: bit.ly/givepodcasts Learn more about your ad choices. Visit podcastchoices.com/adchoices