1840 |
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The Underground Railroad, a secret network of hiding places and routes for helping enslaved persons escape to the North or Canada, is well established by this time. |
1841 |
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George Ripley and 20 others organize a short-lived community, called Brook Farm, in which all share equally in the work while having time for reading and study. This unsuccessful experiment in cooperative living ended six years later. |
1842 |
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The first gummed postage stamps bring changes in the postal system, as senders--rather than the receivers--begin paying for a letter to be delivered. |
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The state of Massachusetts passes a law that limits children under 12, who worked in factories, to a ten-hour day. |
1843 |
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African American Sojourner Truth starts her travels speaking against enslavement. |
1844 |
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Samuel F.B. Morse sends the first telegraph message, from Washington, D.C. to Baltimore, Maryland. |
1845 |
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The first clipper ship is launched, a vessel capable of traveling at double the speed of the older merchant ships. |
1846 |
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Oregon Treaty signed with Great Britain sets the boundary between the United States and Canada at the 49th parallel. |
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War with Mexico begins. |
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Elias Howe invents the sewing machine. |
1847 |
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Thousands of Irish immigrants fleeing the potato famine in Ireland come to the United States.
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Maria Mitchell of Nantucket, Massachusetts discovers a new comet, later becoming the first woman professor of astronomy in the United States. |
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Frederick Douglass, an African American, begins publication of an abolitionist newspaper, The North Star. |
1848 |
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United States wins the Mexican War, acquiring over 500,000 square miles of territory in the Southwest. |
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Women's Rights convention is held at Seneca Falls, New York. |
1849 |
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80,000 people rush to California after gold is discovered. |
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Harriet Tubman escapes from enslavement in Maryland, and becomes an active worker helping other enslaved individuals escape to freedom on the Underground Railroad. |