Last week the British Library was lauded for its impressive  (and graphically extremely polished) effort at bringing 60,000 digital copies of historic books to the general public as a free iPad app. It seems this was just the tip of the Library's plans, however, and it's now entered into an unprecedented deal  with Google  to bring 250,000 other publications to Google Books. The texts are all in the public domain, and some stretch back to the 18th century. It's in the best traditions of the Library's historic mission. And it's not quite as straightforward as merely releasing e-copies of texts.
Google's got several other high-profile deals with other libraries, but the British Library deal is significant because the BL is the second biggest library in the world, after the Library of Congress (if you're counting books, rather than periodicals). There are 14 million books among 150 million texts in a variety of formats and three million are added every year--because the BL is a legal deposit library, so it gets a copy of all books produced in the U.K. and Ireland, including many books from overseas that are published in Britain.
The Library's chief executive Dame Lynne Brindley has commented  on the new deal, highlighting the original mission of the Library to make knowledge accessible to everyone--the Google deal is "building on this proud tradition." Since anyone with a browser can now access the material for free from anywhere in the world, the deal sets an important precedent that may be expanded in the future.
One group who'll immediately benefit from this technology are historians, and historians of language. Putting these 250,000 books into Google not only makes them infinitely more accessible, much faster than before, but it also makes them searchable in ways that haven't been possible. When examining historic writing, it could allow historians to connect to new texts they hadn't encountered before--or find pertinent references inside obscure texts that they wouldn't have previously consulted. Historians of language will be similarly able to access a new dataset to examine trends of word usage and origin.
But we can also assume there are mathematics, science, and engineering tracts among the 250,000 and this could be an invaluable source both for historians of science and current scientists--it's plausible that there is plenty of original thinking that's been forgotten, and which is now only a Google search away.
Global accessibility is also a new angle on these texts, although we can't know yet how China, among others, may censor the content--it's possible that any text referencing time travel  won't be available.
One maneuver this deal allows is that the British Library can now better preserve the originals. Since the full text is going to be digitized, the library could theoretically restrict how often the actual pages themselves are handled. This would mean the books can be kept under tightly controlled climate conditions in the Library's vaults , and thus preserve them for posterity in much better condition.
There's a wrinkle in the terms and conditions  of Google Books concerning the IP of the ongoing digital copy, and it's dogged the project from the start. The new texts are only usable for non-commercial purposes, which means they're not 100% in the public domain as free texts. The copyright of the digital edition remains with Google, although Google promises free access. And that could result in tricky legal issues if Google collapses in the future--although this is unlikely, there's definitely scope for concern about potential legal battles.
The future of reading
Making 60,000 texts immediately readable on your iPad is one thing, and adding another 250,000 is another. The British Library is sending a big signal out about historic texts, and it could subtly change how you think about books. For one thing, student's essays are going to be peppered with even more esoteric quotes from obscure publications as they ill-advisedly Google their way through writing term papers. It also boosts  Google's standing in the "free" books stakes compared to competitors like Amazon, and it does imply that in the future even more of the 150 million texts in the British Library may make it online.