Analyze the extent to which political and economic changes reshaped american society between 1820 and 1848?

19th century, is considered to be the time period between January 1, 1801 according to the Gregorian calendar days of December 31, 1900.
Portugal, and China started to collapse of the Ottoman Empire, Mughal and the Holy Roman Empire ended.
After the Napoleonic Wars, the British Empire, one quarter of the world population, the area has become the world's leading power as the dominant one in three. "Pax Britannica" (British peace) period, has provided the incentive to trade in the world with serious measures against piracy. 19th century but also in the positive sciences, together with new inventions and discoveries has been the scene of a serious breakthrough. Medicine, mathematics, physics, chemistry, biology, electrical and fundamentals of rapid technological innovation in areas such as metallurgy has taken the next century.
Railways began with the urbanization movement in many countries from the start of the industrial revolution, transport and all major cities of the world population, this period has exceeded one million. Developments in the medical field has been also effective herein. The world's remaining undiscovered regions (except for places difficult to reach Antarctica and the Arctic) was discovered and has been instrumental in the world to reveal the precise and detailed map in the 1890s.
This century has caused a rapid decline to live in slavery. British Empire after the Haitian slave revolt, using the rule of the sea and tried to stop the slave trade worldwide. Britain in 1834, the United States, following the civil war in 1865, while Brazil abolished slavery in 1888. Likewise, put an end to slavery in the territory of Russia.

1.  go out into nature and commune with the divine2.  experience real solitude to truly perceive nature3.  realize that individuals are meant to learn from nature and transcend it4.  think of nature as a symbol of the divine