An Eighteenth-Century French Engraving of San Lorenzo, Turin

Gabriel-Pierre-Martin Dumont, after Guarino Guarini, “Plan, et coupe de la chapelle royale du St. Suaire de Turin” [but in fact San Lorenzo, Turin], 1781.
From: [Oeuvres de] Jacques-Germain Soufflot, plate 16.
Source: Bibliothèque de l’Institut National d’Histoire de l’Art (INHA), collections Jacques Doucet / “Licence Ouverte / Open Licence” Etalab

Inspiration for the Panthéon in Paris

This print has fascinated me ever since I discussed it in an article in 2001. The image reproduces the plan and section of Guarino Guarini’s church of San Lorenzo, Turin, based on plates from the architect’s treatise, except the caption misidentifies the building as Guarini’s Chapel of the Holy Shroud (Cappella della Sindone). As the caption goes on to say, Jacques-Germain Soufflot, the architect of Sainte-Geneviève in Paris, had the plate engraved by Gabriel-Pierre-Martin Dumont to bolster the number of authoritative examples for constructing the dome of his church.

Sainte-Geneviève (now the Panthéon) was constructed from 1758-1790, and spirited discussions in the architectural community accompanied the long process of planning and realization. In several meetings of the French academy of architecture, Soufflot defended his plans to construct a large, structurally daring dome over the crossing of the church. In these sessions, he cited multiple precedents that he had seen on his travels throughout Europe: the churches of Notre Dame in Dijon, Toussaints in Angers, Sant’Agostino in Piacenza, San Carlo al Corso in Rome, Christopher Wren’s Saint Mary-le-Bow in London, Milan cathedral, and unnamed churches by Guarino Guarini. From the guidebook published by Soufflot’s traveling companion Charles-Nicolas Cochin, we know that the French architect had been to Turin and had seen both San Lorenzo and the Cappella della Sindone in 1750.

This extraordinary print testifies to Soufflot’s appreciation of Guarini’s structural achievement at San Lorenzo. Since Soufflot hoped to build a dome at Sainte-Geneviève seemingly supported primarily by slender columns, San Lorenzo provided a good example of how to do this. Guarini’s design at San Lorenzo relied on a framework of hidden brick and timber arches to support the dome, rather than placing any significant weight on the marble columns that visually carry the superstructure.

The mistake in the caption was perhaps due to confusion on the part of the engraver Dumont as he produced the print after Soufflot’s death in 1780. Construction of the church continued for another decade until it was completed after the beginning of the French Revolution.

Soufflot’s commission of such an engraving is surprising in view of the criticism of Italian baroque architecture voiced by the French architectural writers in the eighteenth century. French critics targeted Guarini in particular because of his ill-fated, incomplete church of Sainte-Anne-la-Royale in Paris. Nonetheless, Soufflot’s admiration for San Lorenzo demonstrates the power of an innovative architectural solution to transcend polemics based on style, taste, and nationality.

Fredrick Nash, Interior of the Panthéon in Paris, first half 19th century. Watercolor over graphite.
Source: Cleveland Museum of Art / public domain