In this episode, historian Brad Harris compares the horsepower of our modern machines to the power of stallions that helped empires rise and fall for millennia. Travel 30,000 years into the past to witness the first cave paintings of horses, and follow the story through James Watt's steam engine of Industrial Revolution and beyond. By Brad Harris, Historian of Science & Technology. For more information on this episode, including a select bibliography, visit howitbegan.com.