After Paris' city hall was destroyed by fire during the Paris Commune in 1871, the "re-erection" of the building became a priority for the authorities who were anxious to remove all evidence of this dramatic event. The competition organised between 1872 and 1873 stipulated that the old part called "du Boccador" be reproduced "exactly" - it was the first construction of Dominique de Cortone, known as le Boccador, in 1533. It also required the 19th century parts to be retained. The competition was won by Théodore Ballu and Edouard Deperthes.
Ernest Chardon de Thermeau presented a project in collaboration with Marcel Lambert, who was then a student at the Ecole des Beaux-Arts. It was made up of a partial drawing of the project and of a very faded photograph, showing it in its entirety.
The drawing concentrates on the very beautiful elevation of the "du Boccador" section, made up of a central building with a clock tower decorated with sculptures and a three-storey bell tower. The base houses bells whilst the upper level includes a spiral staircase leading to a small belvedere. Two large arcades frame this central part, while forming the lower part of the lateral pavilions.
In the photograph one can detect the extensions of the wings, much more austere in style. Only the corners pavilions once again draw inspiration from the Renaissance style, crowned with triangular and curved pediments.
Chardon and Lambert's project is very important because out of the sixty-six projects submitted, very few of original drawings are preserved in the public archives.