Editing 1842 (section)

=== July–September ===
* [[July 8]] – The total [[solar eclipse of July 8, 1842]] is visible from Asia.
* [[July 13]] – The [[Tri-Kap]] fraternity is founded at Dartmouth College (the oldest local fraternity in the United States).
* [[August 4]] – The [[Armed Occupation Act]] is signed, providing for the armed occupation and settlement of the unsettled part of the Peninsula of [[East Florida]].
* [[August 9]] – The [[Webster–Ashburton Treaty]] is signed between the United States and United Kingdom, establishing the United States–Canada border east of the [[Rocky Mountains]].
* [[August 10]] – The [[Mines and Collieries Act 1842]] in the United Kingdom makes it illegal for women and girls of any age, and boys under ten years, to work underground.
* [[August 14]] – [[American Indian Wars]]: United States general [[William J. Worth]] declares the [[Second Seminole War]] to be over.
* [[August 29]] – The [[Treaty of Nanking]], an [[unequal treaty]] between the United Kingdom and [[Qing dynasty]] China, ends the [[First Opium War]], and establishes [[Hong Kong]] as a British colony (later a British dependent territory until [[1997]]).
* [[September]] – [[Ohio Wesleyan University|Wesleyan University]] is established in [[Ohio]].
* [[September 16]]–[[September 17|17]] – The [[Treaty of Chushul]] ends the [[Dogra–Tibetan war]] (Sino-Sikh War).