The bells in the two towers had been taken out in 1791 and melted down to make cannons. Viollet-le-Duc had new bells cast for the north tower and a new structure built inside to support them. Viollet-le-Duc and Lassus also rebuilt the sacristy, on the south side of the church, which had been built in 1756, but had been burned by rioters during the July Revolution of 1830. The new spire was completed, taller and more strongly built to withstand the weather; it was decorated with statues of the apostles, and the face of Saint Thomas bore a noticeable resemblance to Viollet-le-Duc. The spire was destroyed on 15 April 2019, as a result of the Notre-Dame de Paris fire.