A U.S. academic has uploaded nearly 3 million scanned images from historical books dating back to 1500 for free use on Flickr.

The popular photo sharing site, Flickr, has been updated with nearly 3 million historic images and drawings from more than 600 library book pages scanned by an Internet archive organization. The move is to preserve the legacy of the original images in the books that have been ignored in favor of the texts. Some books are so ancient, they date back to 1500, but the lack of interest has resulted in damage or loss.

Kalev Leetaru, a scholar at Georgetown University, took the initiative to scan the historic images in the books and ensure their existence forever. Leetaru has already uploaded 2.6 million images on Flickr and made them copyright free. More than 9 million images will soon be joining the extensive historical gallery on the photo sharing site.

"For all these years all the libraries have been digitising their books, but they have been putting them up as PDFs or text searchable works," Leetaru told the BBC.

"Stretching half a millennia, it's amazing to see the total range of images and how the portrayals of things have changed over time," he added.

Digitalization of the images in the books changes the way historical books have been preserved for their text until now. Thanks to the automatic tags with full description, users can search particular images using a single search term.

In an official Flickr blog, Internet Archive detailed how the new project to digitalize imageries of half a millennium of books began.

"Searching for love yields a myriad images of cherubs and courtship, while mortis (death) offers a glimpse into the early modern period's fascination with the subject," Internet Archive wrote in its blog explaining the search process. "A search for bird offers a vividly colorful showcase of the world's bird species, while searching for telephone traces the invention's history from its introduction as an electric novelty to its widespread adoption."

Enthusiasts can browse through the rare, relic images from history here.