Michel Ferdinand d'Albert, 5th Duke of Chaulnes

[4] He commanded the light cavalry of the Maison du Roi (English: King's Household).

His estate contains a remarkable amount of rare and curious items collected from Egypt, Greece, China, including Etruscan vases of all types, antique bronzes and natural history specimens.

Two years after, he published a memoir in article form which described his experiments, and was included at the beginning of Newton's Opticks Bk.

In this work he described his discovery of the peculiarities of the diffraction of light rays reflected by a concave mirror and how they might be stopped by a board pierced in the middle.

[6] He married Anne Josèphe Bonnier (1718–1787), who replaced the Viscountess of Beaune in 1766 as one of Queen Marie Leszczynska's ladies-in-waiting.