Christ's College, which is part of Cambridge University, was founded in 1505. The ghost of Christopher Round, who was a fellow of the college in the 1800s, haunts its grounds.

Round and another academic once spent a morning conducting scientific experiments with the newly discovered chemical chloroform. The gentlemen disliked one another as they were equally keen on an attractive local lady.  Round's colleague became rather inebriated by the chloroform fumes, and as they were walking home through the college grounds, he drunkenly fell into the swimming pool. Round seized an opportunity to get revenge on his fellow suitor, and grabbed a branch to prevent him from surfacing from the water. His enemy drowned quickly.

This wicked deed caused Christopher Round to eventually feel extremely remorseful, and his ghost walks sorrowfully through the grounds of Christ's College to this day, circling the pool and the old mulberry tree.