I am pretty sure that many of you are interested in art, and more particularly, in painting. Of course, I am not going to discuss the art of painting here, but I found an interesting piece by Paul Delvaux, a Belgian painter:

The painting, from 1957, is called Trains du Soir (Night Trains). If you look carefully at the picture, you might find something unusual, something that doesn’t look right; I am not speaking about technique or realism, but about science.

Will you find what’s wrong with this picture?