Publications [#268055] of Henry Petroski

Papers Published

1. Petroski, H, The Evolution of Eyeglasses Applying the principles of optics to a basic human need required both imagination and skill, American Scientist, vol. 101 no. 5 (2013), pp. 334-337, Sigma Xi, ISSN 0003-0996 [doi]
   (last updated on 2023/06/01)

   Abstract:
   The invention of eyeglasses is credited to Edward Rosen, a classicist turned historian of science. According to Rosen, the oldest known reference to a pair of eyeglasses occurs in a sermon preached in Florence, Italy, in 1305 by Friar Giordano da Rivolta, whose monastery was St. Catherine in Pisa. The ability of a segment of a glass sphere to magnify whatever is placed before it was known around the year 1000, when the spherical segment was called a reading stone. Turning a couple of magnifying glasses into a pair of spectacles required the innovation of mechanically linking two mounted magnifying lenses. By pivoting the glasses about the rivet, the angle between the handles could be adjusted so that the parts of the spectacles over the nose and eyes would fit a wearer's need. This awkward feature of the earliest eyeglasses was overcome by a variety of means to hold the lens frames in place on the wearer's head. By the 18th century the use of steel, which has significant springiness compared with bone, leather or bronze, introduced a new way to connect two framed lenses.