Modern Marvels: In a carnivorous world, a butcher is a necessary link in the food chain, carving a carcass of unsavory flesh into mouthwatering cuts. We trace the grisly trade's evolution--from yesteryear's butcher-on-every-corner to today's industrial butcher working on a "disassembly" line. We tour the infamous remains of the Chicago Stockyards, where Upton Sinclair, Clarence Birdseye, and refrigeration changed butchering forever; witness high-speed butchering; and travel to a non-stop sausage factory. And if you're still squeamish, a USDA inspector offers the lowdown on HACCP--the country's new system of checks and balances on everything from quality grading to E. coli, Salmonella, and Mad Cow Disease. Finally, we visit the last bastion of old-school butchering--the rural custom butcher, who slaughters, eviscerates, skins, and cuts to his customer's wishes.