As the second week of the final Grand Slam tennis tournament of the year moves closer to crowning champions in New York, archivists across the Atlantic Ocean at the University of Glasgow in Scotland have discovered what may be the earliest printed pictures of the game of tennis.

The images were found in a French book published in Paris in 1540 and just recently acquired by the University Library. The 16th century book by Guillaume de La Perriere , is titled “Le theatre de bons engins” or “The theater of fine devices”. The pictures show a game that’s a precursor to the modern game of tennis — jeu de paume, or game of palms, played with a much shorter racket and much bulkier clothing.

University of Glasgow professor Laurence Grove described the picture book as “Instagram for the 16th century,” and that the images came as a total surprise to archivists.

“You never know what’s in there. There are some funny images, and they remind us that what you think is modern isn’t modern. It’s been there for four centuries,” Grove said.

The book includes a range of pictures on different subjects, all accompanied by mottoes or sayings about life in general. One page highlights a moth and candles and warns against rushing into war.

Scotland is also home to the oldest tennis court in the world, built for James V, King of Scots, at Falkland Palace in 1539.