Prior to New York City's Commissioners' Plan of 1811, the city's Common Council in 1797 commissioned city surveyors Casimir Goerck and Mangin to survey the streets of the city; Goerck died of yellow fever during the course of the surveying, but Mangin completed it and delivered the draft of the Mangin–Goerck Plan to the Council in 1799 for correction of street names; the final engraved version would be presented to the Council in 1803. Unfortunately, Mangin had gone beyond the terms of the commission, and the map not only showed the existing streets of the city, but also, in Mangin's words, "the City ... such as it is to be..." In other words, the plan was a guide to where Mangin believed future streets should be laid out.
The Council accepted the Mangin–Goerck Plan as "the new Map of the City" for four years, and even published it by subscription, until political machinations perhaps organized by Aaron Burr, the political enemy of Mangin's mentor Alexander Hamilton, brought the plan into disrepute, and the Council ordered that copies which had already been sold be bought back, and that a label warning of "inaccuracies" be placed on any additional copies sold. Nevertheless, as the city grew, the Mangin–Goerck Plan became the de facto reference for where new streets would be built, and when the Commissioners' Plan was revealed in 1811, the area of the plan which the public had been warned was inaccurate and speculative, had been accepted wholesale by the commission, their plan being almost identical to Mangin's in that area.
