This is a piece of the iron chain with which Samuel Brown fitted out a naval vessel, the 'Penelope', in 1808, in order to prove that iron chain was superior to hempen rope. The ship sailed to the West Indies, and it was shown that the iron chain was stronger than rope cable, easier to handle, and cleaner. The fumes from wet and dirty rope had caused sickness and even death in hot climates. The Royal Navy began to change over to chain cable, and merchant ships followed.