It took a quarter of a century, nearly two hundred lives, and a wealth of innovative ideas to dig the four-and-a-half-mile Hoosac Tunnel through a Massachusetts mountain
Until 1880 a model had to accompany every U.S. patent application, and each had to be evaluated for “novelty, originality, and utility.” To see how this was done, our author put himself in the place of the patent examiners who were responsible.
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