Perhaps the reference is to the later work of the choir of St. Etienne Beauvais, perhaps to the work of Martin Chambiges in Beauvais Cathedral of St.-Pierre (as opposed to the church of St. Etienne to which Ruskin refers at Notebook M p.15), and the West Front of Troyes in around 1500, called by Stephen Murray ‘the triumphant last flourish of Gothic’ (see Murray).
For images of Troyes see here.
For an image of St. Pierre see:
Chambiges had some involvement in approving the reconstruction of the church of Church of St-Gervais-St-Protais at Gisors, on which see Notebook M2 p.3L and Notebook M2 p.135.
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