This week we're thinking about what it means to be a trader in today's electronified markets and contrast it with trading in the era of horse and buggies. That's right, we're going back in time to talk mule trading and the story of the legendary Ray Lum, who spent years buying and selling livestock all over the U.S. in the early 1900s. William R. Ferris, history professor at the University of North Carolina and author of Mule Trader: Ray Lum's Tales of Horses, Mules, and Men, tells us about Lum's adventures in the South, including the purchase and transportation by train of 80,000 mules from South Dakota to New Orleans. He explains why the "trader is the poet of capitalism," how the term "day trader" can be traced to stable storage trades and why some things—like boozy dinners between brokers and their clients—never seem to change. It's arbitrage of the animal sort, with storage trades thrown in to boot.Along the way, we ask whether traders provide a social service and explore the trade-off between modern efficient markets and the bygone era of 100 percent mark-ups on (mule) trades.