A prominent French architect and structural engineer, Alexandre-Gustave Eiffel (born on December 15, 1832 in Dijon, France) was the second designer of the internal structural elements of the Statue of Liberty. In his early work designing railway bridges, Eiffel relied on sophisticated mathematical designs renowned for their lightness, grace, and strength.
When the Statue of Liberty's initial internal designer, Eugène Viollet-le-Duc, unexpectedly passed away in 1879, the Franco American Union and Frédéric-Auguste Bartholdi hired Eiffel as his replacement. While Eiffel praised and retained Viollet-le-Duc's plans for the sculpting and connection of the copper sheets (he would use Viollet-le-Duc's repoussé technique and armature bars), he ultimately changed the initial plans for the interior design in favor of a modern approach. The Statue's new internal structure would not rely on weight to support the copper skin but rather a flexible, skeletal system.