At a time when polite society wouldn't dream of hanging women's and men's underwear on the same clothesline, a Minnesota manufacturer dared to advertise the unmentionable. "Don't Say Underwear," crowed the ads, "Say Munsingwear " Consumers of the 1890s responded. The company's wildly popular "itchless" union suits represented a truly revolutionary advance. When fashion and central heating changed the market, Munsingwear offered silk and nylon...