Ballast Pond, Torpoint, Cornwall
This ballast pond was built by the Admiralty in 1783. Ships carried ballast (stone and sand in the 18th century) to keep them stable particularly when they had no cargo. When repairs were done to the bottom of a ship much of the ballast would have to be removed. It was taken off into lighters (a type of small boat), which would often be heavily laden. It is presumed that the ballast pond was built as a shelter for the lighters. They would not then need to be unloaded but could remain in the dock until the ballast was needed again.