C O P Y I N G
E N L A R G I N G
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R E D U C I N G

Proportional Divider, used for enlarging or reducing drawings by direct measurement and for dividing circles into equal parts. As illustrated, it consists of two legs pointed at each end and hinged somewhere near the middle. The hinge joint is made adjustable to suit any ordinary ratio of reduction or enlarging which may be desired. These instruments were generally provided in the better quality sets up until the early 20th century.