Grenoble, 24 August 1924.
Émile sees the first signs of the tower rising from the ground. A month later, it has already grown. Intrigued by its growth of 3 metres a week, Émile decides to go and meet the site manager to ask him a few questions. They talk on the edge of the building site. Émile asks Mr Nadaud about the tower's rapid progress. He replies that it all starts with the foundations. Beneath their feet, a structure made up of 72 piles, each 15 metres long, forms the foundation of the building. He then explains that the architectural design is of paramount importance. Unadorned, with its framework of eight pillars and its straight lines, the tower's features make it easy to assemble. 'Thinking about architecture means thinking about construction': Perret's words are therefore embodied in this new project. It is an architecture conceived with its own construction process in mind.
Next, Mr Nadaud continues his explanation by highlighting another technical aspect. He states that the main tool is a concrete formwork module that moves from level to level as the building rises. This repetitive construction process is essential and, combined with the materials – 700 cubic metres of concrete – and the workers' expertise, the tower rises steadily. An authentic photograph of the construction workers brings his speech to a close.
In October 1924, Léon Jaussely, the exhibition's chief architect, questions the structural calculations underlying the tower's design. Following a review, and a comparison with those of the Eiffel Tower, the calculations are deemed correct and work continues. And so, on 4 May 1925, the tower is officially opened. As is customary amongst construction workers, a bouquet is placed at the top of the tower to mark the work's completion and honour its author, 'the man of reinforced concrete'.