Big Apple
Although the history of "Big Apple " was once thought a mystery, a clearer picture of the term's history has emerged due to the work of amateur etymologist Barry Popik, and Gerald Cohen of Missouri University of Science and Technology. A number of false theories had previously existed, including a claim that the term derived from a woman named Eve who ran a brothel in the city. This was subsequently exposed as a hoax.
Manhattan
New York grew as an economic center, first as a result of Alexander Hamilton's policies and practices as the first Secretary of the Treasury and, later, with the opening of the Erie Canal in 1825, which connected the Atlantic port to the vast agricultural markets of the Midwestern United States and Canada. By 1810, New York City, then confined to Manhattan, had surpassed Philadelphia as the largest city in the United States.
Tammany Hall, a Democratic Party political machine, began to grow in influence with the support of many of the immigrant Irish, culminating in the election of the first Tammany mayor, Fernando Wood, in 1854. Tammany Hall dominated local politics for decades. Central Park, which opened to the public in 1858, became the first landscaped public park in an American city.