Here are some one liners...
St. George of the Mine and the Price of Milk -- The Portuguese build a combination castle and trading post near a gold mine in what is now Ghana. It will also be a trading post for slaves. I then talk about the economics of slavery, oil prices and the reason milk farmers might want to pour their product on the ground occasionally.
The Tower and the Search for the Northwest Passage -- A tower is built as part of a wall along the port in Amsterdam. It will one day become the launch point for Henry Hudson as he searches for the Northwest passage to the Pacific Ocean.
Euclid's Elements in Print -- It is probably the second most important book ever to be set to print. It will remain required reading until the 20th century. I also talk a little bit about non-Euclidean geometry but not too much.