His influential business partner, Matthew Boulton, even got the patent extended by lobbying Parliament.5 Boulton and Watt used it to extract licensing fees and crush rivals—among them Jonathan Hornblower, who made a superior steam engine yet found himself ruined and imprisoned. The details may have been grubby, but surely Watt’s famous invention was worth it? Maybe not. The economists Michele Boldrin and David Levine argue that what truly unleashed steam-powered industry was the expiration of the patent, in 1800, as rival inventors revealed the ideas they had been sitting on for years.
