the population, are said to have fled the city during the epidemic. 1833 – Harper & Brothers publisher in business. 1834 July: Anti-abolitionist riots (1834). Convention for the Improvement of the Free People of Color held. Park Avenue Tunnel (roadway) opens. Cornelius Van Wyck Lawrence becomes mayor. 1835 December 16: New York Stock Exchange and hundreds of other buildings are destroyed by the Great Fire, which rages for two days in the Financial District. Efforts to stop the fire are limited by sub-zero temperatures, which freeze water in hoses, wells, and the East River. Twenty-three insurance companies are wiped out by the resulting claims. School of Law of the University of the City of New York established. 1836 Union Theological Seminary founded. Astor House hotel in business. 1837 Flour riot of 1837 destroys 500–600 barrels of flour and 1,000 bushels of wheat. 1838 Rutger's Institute established. Halls of Justice built. Tombs Prison begins operating. Opening of Green-Wood Cemetery in Brooklyn. 1839 Astor Library founded. Sunday Mercury newspaper begins publication. 1841 July 25: Mary Cecilia Rogers, a young woman known popularly as "The Beautiful Cigar Girl", disappeared and her dead body was found floating in the Hudson River three days later. The details surrounding the case suggested she was murdered. The death of this well-known person received national attention for weeks. The story became immortalized by Edgar Allan Poe in his story "The Mystery of Marie Roget". Despite intense media interest and an attempt to solve the enigma by Poe, the crime remains one of the most puzzling unsolved murders of New York City. 1842 Croton Aqueduct begins operating. Barnum's American Museum and Dodworth dancing school in business. Philharmonic Society of New York and Board of Education established. 1844 Brady photo studio in business. New York Yacht Club founded. 1845 Bowery Theatre opens. New York City Police Department, and New York Art Union established. Fire. 1846 – Stewart Dry Goods Store built. 1847 Free Academy of the City of New York founded (later City College of New York). Madison Square Park and Astor Opera House open. Grace Church built. 1848 December: Cholera outbreak begins, its spread initially limited by winter weather. By June 1849, it reaches epidemic proportions. 5071 city residents are killed. Associated Press established. Trow's Directory of New York City begins publication. Goupil Gallery branch in business. 1849 – May 10: Astor Place Riot. 1850s–1890s 1850s–1860s 1850 Winter Garden