It looks like the legendary The Grammar of Ornament has been scanned and made available on the web. The version on Dover Books has been available for years, but it is great that these images are available digitally.
I love to see books that were once contemporary encyclopedias on the history of visual images, but have since become a part of history themselves... The illustrations are amazing, but artist's illustrations of historical artifacts are always going to be skewed by the artist's hand, showing just a little bit of the visual culture and upbringing of the illustrator him/herself. For instance, a 19th century illustrator is going to depict a scene from history differently than would a 21st century illustrator... These differences are what is interesting to me when I look at these images.
The book begins with pre-history and ends around the time of the late 1800's Arts and Crafts movement.
The Grammar of Ornament (1910)
Jones, Owen, 1809-1874
The Grammar of Ornament