RRS Discovery in Dundee

You're standing at Discovery Point in Dundee, right in front of RRS Discovery. Take a look at that wooden hull and those three masts. She was launched here on the Tay in 1901, the last traditional wooden three-masted ship ever built in Britain. Back then, people called her the strongest wooden ship ever made. In places the hull is more than two feet thick, built up from layers of oak, pine, elm and greenheart. Notice anything missing? There are no portholes. They would have weakened the hull, so light and air came in through mushroom-shaped vents on the deck.