(1817–85). Parisian architect, renowned for the early Renaissance-style La Trinité Church (1861–7) near the Gare St-Lazare in Paris. Ballu completed Gau's Ste-Clotilde (1846–57), the first Gothic Revival church in Paris; restored the Tour St-Jacques de la Boucherie (1854–8); and designed the Flamboyant Revival free-standing tower, and restored the rest of the fabric of St-Germain I'Auxerrois, with its lantern-top, beside Hittorff's Mairie du Ier (1858–63). He also built the Hôtel de Ville, Paris (1874–82).
From A Dictionary of Architecture and Landscape Architecture in Oxford Reference.