Hyperboloid with one surface

Théodore Olivier devoted his life to the promotion of descriptive geometry. In this respect, he followed in the footsteps of Gaspard Monge, one of the founders of the École Polytechnique, where he taught his theory of surfaces and their curvature. According to Olivier, this discipline enabling ‘reading’ in space was essential for the training of engineers if France’s industrialisation was to catch up with England’s. Founder of the École Centrale des Arts et Manufactures in 1829 and a teacher at the Conservatoire des Arts et Métiers, Olivier commissioned the mathematical instrument maker Hippolyte Pixii to construct articulated geometric models representing a series of surfaces and their modifications. The model on display visualises a cylinder’s transformation into a cone: the rotation of the upper circle creates a hyperboloid out of the two volumes.