Penny suggested that we should add the Flickr Commons pictures to the search in the book writing wizard here at Tar Heel Reader. That category didn’t exist back when I was writing that part of the code (or at least I didn’t see it). It turns out the addition was trivial. So now your searches will include the huge collection of pictures with no known copyright. Check out the Flickr Commons page for the the list of institutions participating. Thanks Penny for a great suggestion.