Elliptograph by Sir Charles Vernon Boys, 1880-1920.
© Science Museum / Science & Society Picture Library
The elliptograph, or ellipsograph, was developed to make smaller ellipses than were capable with elliptical trammels, an earlier drawing instrument. The elliptograph is a machine for drawing small ellipses, the shapes seen when circles are viewed in perspective. They became popular during the first half of the 19th century as the demand for engineers and architects increased. Sir Charles Vernon Boys (1855-1944) was a physicist and instrument maker, best known for his determination of the gravitational constant in 1897.