Model for Descriptive Geometry by A. Jullien - Angle between a Horizontal Line and another Line

The horizontal line is represented by the wire coming out of the vertical plane at c’. The second line would run from point a on the horizontal plane to b’ on the vertical, however the black string that should represent this line is missing. The two lines intersect at point (m, m’) at the bend in the wire. Lines cd and ab are the projections of the lines on the horizontal plane, with line nm perpendicular to cd at m. By rotating about these three lines as in relief 25, the angle between the given lines is shown on the horizontal plane as angle aM2D1.
For more details, see COLL.1986.0885 and 1986.0885.01.01.
Currently not on view
Object Name
geometric model
date made
ca 1880
Jullien, A.
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
place made
France: Île-de-France, Paris
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, Kenneth E. Behring Center

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