Abstract: This article is an ecopoetic exploration of “Le Maçon”, one of Gaspard de la Nuit's best-known compositions. We propose a comparative encounter with the poems of Poncy (Marines, 1842, Le Chantier, 1844), Ségalas (Nos bons Parisiens, 1864) and Blanchecotte (Les Militantes, 1875). The mason, somewhere between a modest worker and a powerful demiurge-demolisher, is here understood as a key figure in the creation and destruction of nineteenth-century urban landscapes and as an essential agent in humanity’s progress.