Ruskin in Modern Painters criticizes Claude Lorrain's perspective in two of his paintings (Embarkation of the Queen of Sheba and Seaport with the embarkation of St. Ursula). Specifically, Ruskin says that "the quay on which the figure is sitting, with his hand at his eyes is egregiously out of perspective."
Here is a link
to the painting. Do you agree with Ruskin?
Also, he says that the curved portico in the second painting is out of perspective. Here
's a link to the painting. What do you think? I'm finding it hard to locate the errors that Ruskin points out.