Today marks the sequicentennial, or 150th anniversary, of the date of publication of Charles R. Darwin’s most-sold book, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. The original printing of 1,250 copies sold out immediately. I just checked Amazon.com, where it is right now sitting at the #10 bestselling science book position.
You don’t have to buy a printed copy to read it, though. I first got an etext through an archive at Oxford, and Project Gutenberg has long had one of the editions. But for the most of Charles Darwin’s works to be had online, head over to John van Wyhe’s fantastic site, curiously enough called Darwin Online.