1840s

First use of general anesthesia in an operation, by Crawford Long The first electrical telegraph sent by Samuel Morse on May 24, 1844 from Baltimore to Washington, D.C.. First signing of the Treaty of Waitangi (Te Tiriti o Waitangi) on February 6, 1840 at Waitangi, Northland New Zealand. The treaty between the British Crown and Māori made New Zealand a British colony and is considered the founding point of modern New Zealand. The Webster-Ashburton Treaty, signed August 9, 1842, settled the dispute over the location of the Maine-New Brunswick border between the United States and Canada. On August 29, 1842, the first of two Opium Wars ended between China and Britain with the Treaty of Nanking. One of the consequences was the cession of parts of modern day Hong Kong to the British. Hong Kong would eventually be returned to China in 1997.