I just love finding apps like this, and I think you'll be excited too. The British Library has released 1000 books from its 19th Century collection into a free iPad app that includes novels, historical works, poetry, philosophy and scientific books.
The books have been scanned in high resolution and color so you can see the engraved illustrations, the beauty of the embossed covers, along with maps and even the texture of the paper the books were printed on.
You can search the collection, browse titles by subject, and even read commentary on some of the titles. The books can be downloaded for reading offline.