Photo of a 'Pascaline', the mechanical calculator invented and manufactured by French scientist Blaise Pascal around 1642. From the accompanying text: "The machine has been reversed, and the bottom of the casing, which is hinged, thrown back, showing the numeral wheels and gearing of the different orders, and the transfer levers for the carry of the tens." The gearing worked similarly to a car's odometer. Alterations: removed frame and figure number, rotated image to justify, and increased brightness.