Public and Private Libraries all over the World are now in the process of saving books in their archives over to various formats to be accessed over the internet. Most are free downloads, I have been downloading these books to my computer for transfer to CD's using the free "Adobe Reader" program for viewing.
The reason for this massive undertaking by the World's Libraries, is that time is slowly destroying these books that are over a hundred years old!
Many of these books where never published in large numbers, many only had less than a thousand ever printed, and those that have survived over time, ended up in private collections that were later donated to Universities with the death of their original owner.
Even the United States "Library of Congress" is in the process of converting decaying books and manuscripts to PDF that can be viewed and downloaded by the public!
Currently I have over a hundred PDF "Fly Fishing" related books on CD now....
~Parnelli