Nocturne has been dated about 1875/1877. 1

It is difficult to date, but the technique – the lack of imprimatura and the lack of paint runs – could argue for an early date. 2

Nocturne, The Hunterian

Nocturne in Blue and Gold: Valparaiso, Freer Gallery of Art

Nocturne in Blue and Silver: The Lagoon, Venice, Boston Museum of Fine Arts

The composition is comparable to Whistler's Valparaiso nocturnes of 1866, such as Nocturne in Blue and Gold: Valparaiso Bay [YMSM 076] (which was probably completed in the late 1870s), and the technique of his Venetian Nocturnes of 1879/1880, such as Nocturne in Blue and Silver: The Lagoon,Venice [YMSM 212]. A date in the late 1870s is most likely.