Mathematical Treasure: Coradi Suspension Pantograph

Suspension Pantograph Used by Mary Spear, manufactured before 1928, Smithsonian Negative Number NMAH-AHB2016q012400.

The pantograph is a drawing instrument used to enlarge and reduce figures. It was devised by the Jesuit astronomer and mathematician Christoph Scheiner in 1603 and described by him in a 1631 publication. Pantographs in the Smithsonian collections date from the 19th and 20th centuries, although the instrument is still sold today. They were used especially by draftsmen, printers, and designers (including designers of textiles).

The pantograph shown was made by the Swiss firm of G. Coradi by 1928 and sold by Eugene Dietzgen Company of Chicago. It was used by Mary E. Spear, a draftsman who worked for the Internal Revenue Service in Washington, DC. She is also known for her 1969 book Practical Charting Techniques.

This object and other pantographs in the collections of the Smithsonian’s National Museum of American History are discussed in some detail at the website www.si.edu/spotlight/pantographs.

Index to Mathematical Treasures

Index to Mathematical Objects