Model for Descriptive Geometry by A. Jullien - Angle between Two Planes

The given planes are APA’ and BQB’. The vertical and horizontal projections of the planes meet at the points d’ and c on the vertical and horizontal planes respectively, with line of intersection of the two planes cd’, depicted by the red sting. Point n is the foot of the perpendicular from the line to the horizontal plane. The red string that runs left to right indicates the plane perpendicular to line cd’ with segments on the given planes. By rotating this perpendicular plane down to the horizontal plane, the angle between the two given planes is the angle tM2s.
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


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