W. C. Stewart's The Practical Angler, first published in 1857 is now in the public domain and has been scanned by Google Books. You can view it online here http://books.google.com/books?id=Pz8CAA ... h7#PPP1,M1 and download it in a .pdf file. Three editions are available, the link above is to the 1874 edition, which is the latest available online.

W. C. Stewart is best known for his three spider patterns (black, red and dun) and for advocating fishing upstream rather than down. The book also has dressings for three winged flies, which along with the three spiders, are all the patterns Stewart thought necessary.