John Green wraps up revolutions month with what is arguably the most revolutionary of modern revolutions, the Industrial Revolution. While very few leaders were beheaded in the course of this one, it changed the lives of more people more dramatically than any of the political revolutions we've discussed. So, why did the Industrial Revolution happen around 1750 in the United Kingdom? Coal. Easily accessible coal, it turns out. All this, plus you'll finally learn the difference between James Watt and Thomas Newcomen, and will never again be caught telling people that your blender has a 900 Newcomen motor.