Sargent Hall, Boston Public Library.

Here's a wonderful book research site if you have an e-reader or don't mind reading on a computer screen. While it's great for general literature ("Varney the Vampire," E.T.A. Hoffmann's "The Cremona Violin," Goethe's "Italian Journey," and numerous others that must be read before turning out the light,) the site's breadth for art research is impressive:

The Training of Memory in Art, Horace Lecoq de Boisbaudran

Remember to change the search criteria from "American Libraries" to "Texts."