Model for Descriptive Geometry by A. Jullien - Angle of a Plane with Planes of Projection

Given plane APA’, c’ is a point on the intersection line of the plane with the vertical plane. Point b on the horizontal intersection of the plane is chosen so it that bc’ is perpendicular to PA. Connect b and c’ to from the red string. The horizontal projection of bc’ is bc and the vertical projection is cc’. By rotating bc’ about bc to the horizontal, point C1 is found. Now angle cbC1 is the angle of the plane with the horizontal plane. Similarly, the angle bC1C is the angle with the vertical plane.
For more details, see COLL.1986.0885 and 1986.0885.01.01.
Currently not on view
date made
ca 1880
Jullien, A.
place made
France: Île-de-France, Paris
Physical Description
paper (overall material)
metal (overall material)
overall: 6.5 cm x 7.5 cm x 6.5 cm; 2 9/16 in x 2 15/16 in x 2 9/16 in
ID Number
catalog number
accession number
descriptive geometry
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Jullien Geometric Models
Data Source
National Museum of American History