1956 Chevrolet Bel Air Convertible

Drop the top, and cruise like a movie star! It sounds like fun. But movie stars live in sunny California -- most of us don't. Convertibles may draw people into showrooms, but sedans take them home. In 1956, only about 2.6 percent of Chevy customers drove home in ragtops. Despite that fact, the carefree appeal of 1950s convertibles has made them a symbol of that era.

The 48,000-mile Interstate Highway System connects all corners of the United States with high-speed, limited-access roadways. Funding for new construction and ongoing maintenance comes from taxes on vehicles, tires, and -- mostly -- fuel. But as cars get more efficient and drivers shift to hybrids and electrics, gas tax revenues get smaller. Highway funds shrink as the costs of caring for an aging system grow.

This car symbolizes 1950s America: a time of exuberance, self-confidence, excess, and self-indulgence. Cadillac designers drew on jet aircraft for ideas, from the sharp, swept-back tailfins to the front parking lights that resemble B-52 bomber air intakes. Under that jet-inspired skin is a 345 horsepower engine, air suspension, and a host of luxury options, including an automatic headlight dimmer. We are unlikely to ever see such cars again.

Spinning frames spin cotton fiber into yarn and then wind it onto a bobbin. This throstle spinning frame could simultaneously spin 64 strands of yarn. (Throstle -- an old name for a song thrush -- refers to the bird-like sounds the machine made.) Machines like this helped produce the large quantities of yarn that growing industrial weaving operations needed in the early and mid-1800s.