Copper sheathing<span> is a practice of protecting a under-water hull of a ship or boat from the corrosive effects of salt water and bio fouling through the use of </span>copper<span> plates affixed to the outside of the hull.
It was pioneered and developed by the Royal Navy during the 18th century.
Hope this helps.</span>
In the nineteenth century, Mexican American, Chinese, and white populations of the United States collided as white people moved farther west in search of land and riches. Neither Chinese immigrants nor Mexican Americans could withstand the assault on their rights by the tide of white settlers.