This is the story of how a Pittsburgh steel worker became the lensmaker behind some of the most important experiments of 19th century physics. John Brashear fell in love with the night sky as a kid in the 1840s. Though he took a job as a millwright, in his free time, he and his wife dedicated themselves to making a telescope lens so they could view the stars. With only an elementary education (and the mentorship of Samuel Langley at the Allegheny Observatory), John became one of the world’s p...