The battle you are referring to is actually called the Battle of the Ironclads. In this battle, it was the Merrimac (from the Confederacy) versus the USS Monitor (from the Union). This was the first battle between iron-fortified vessels in the Civil War. This battle ended up in a draw but represented a new form of fighting that both the Union and Confederacy had to be ready for.
They feared the revolutionary violence would spread to Britain.
Established when the Han Dynasty in China officially opened trade with the West in 130 B.C., the Silk Road routes remained in use until 1453 A.D., when the Ottoman Empire boycotted trade with China and closed them.