In 1849 Britain's Navigation Acts were repealed, allowing ships of other nations to carry goods to and from British ports, and this brought even greater competition into the shipping world.
一八四九年英國航海法案撤銷，各國船隻自此皆可往來英國口岸運貨，帶來了航運界更大的競爭。美國在這場白熱戰中拔得頭籌。