Unpublished letter, regarding a way of building vaults from J [Jean] Giral to unknown recipient Giral explains that he wrote his work on building vaults whilst designing the decoration for the Place Royale du Peyrou [Promenade du Peyrou, Montpellier, France]. He attempts to provide a solution to building vaults with multiple arches. Subject: Engineering / Architecture Written by Giral in Montpellier, Languedoc [France]. 9 August 1780