Room interiors so detailed you could walk right in and sit down. American. Walter Gay, artist (1856-1937). A friend of John Singer Sargent with whom he studied under Léon Bonnat.

"The Fragonard Room at the Frick Collection." 1926.
“The Fragonard Room at the Frick Collection.” 1926. Collection of the Frick, Pittsburgh. In the public domain due to age. via https://artsandculture.google.com/asset/the-fragonard-room/2wEAUIeWAaAFeQ
"Galerie des Bustes, Château du Reveillon." 1907-1909.
“Galerie des Bustes, Château du Reveillon.” 1907-1909. Oil on canvas. In the public domain in the United States because the artist died over 70 years ago. via https://commons.wikimedia.org/wiki/File:Walter_Gay_-_Galerie_des_Bustes,_Chaeau_du_Reveillon.jpg
Les-Tableaux-Le-Breau-Walter-Gay-oil-painting-768x629
“Les Tableaux Le Breau.” ca. 1918. Collection of the Dumbarton Oaks Research Library and Collection. In the public domain in the United States because the artist has been dead over 70 years. via https://www.oceansbridge.com/shop/artists/g/ga-gaz/gay-walter/les-tableaux-le-breau
La Robertsau. 1908. American. Oil on canvas. Walter Gay, painter (1856-1937). Signed Walter Gay on the lower left. Image © CHRISTIE’S 2024. Fair use license. via https://www.christies.com/private-sales/privateitems/La-Robertsau-SN00653380-001