So, in 1807, they acted again. Optimists at that time expected the city's population, then around 95,000 people, to expand to 400,000 by 1860, when, in fact, it reached 800,000 before the beginning of the Civil War. Faced with opposition and conflict from various political factions, including property owners whose private deeds conflicted with the property lines of the Mangin–Goerck, and the reality that any plan the Council came up with could be overturned by a subsequent Council, the city asked the state legislature for help. The Council said its goal was "laying out Streets ... in such a manner as to unite regularity and order with the public convenience and benefit and in particular to promote the health of the City ... allowing a free and abundant circulation of air" to stave off disease, as at the time, foul air, or "miasma", was thought to be the cause of many diseases, and the city had lived through decades of epidemics of yellow fever.