At 20 minutes: the number 204 on the locomotive and its tender is shown in mirror image showing that the clip has been flipped.
At the start of the film, the Wisteria is in bloom, suggesting that it is late spring; however, Colette's mother asks her to pick some blackberries, which would not be ripe for picking until late summer/early autumn.
Willy's name is pronounced "Willie" by all the characters, but it was actually pronounced "Villy".
In the dance studio scene, which takes place in 1904, a pianist is seen playing Golliwog's Cake-walk by Claude Debussy (repeated by orchestra in the soundtrack). The piece was not composed until 1909.
The musical setting of Yeats' poem "Down by the Sally Gardens" was published in 1909.
At the beginning of the film, set 1892 the main character is given a snow globe. The snow globe was invented in 1900 by Austrian Erwin Perzy.
At the point of the film in 1905 at the train station there is more than one woman smoking on the platform. It wasn't socially acceptable for women to smoke until 1929.