At the very dawn of mechanically powered vehicles, the English engineer George Stephenson had a related idea, and he made it work more than 200 years ago. Because they lacked springs to absorb shocks, early locomotives were breaking both their own structures and their rails, but including such metal springs would have to await the availability of better, more crack-resistant materials. Stephenson’s alternative was to support his locos by boiler pressure, acting on pistons in close-fitting cylinders. The system seems to have worked fairly well, as it continued into the early 1820s. As the engine raised steam before a run, boiler pressure would rise, and so would the locomotive.