Read an excerpt from this article below. You can download the full article by using the link at the end of the excerpt.
The earliest modern application of the land-use zoning power in the United States was initiated in 1867 in San Francisco to isolate obnoxious land uses in such a way as to protect the environment, both physical and social, of existing residences.
The physical separation and isolation of dangerous, odoriferous, or unsightly practices, such as tar boiling, soap making, fat rendering and dead carcass cremation, was viewed at that time as a reasonable governmental response to the unacceptable impositions of one otherwise legal activity upon another. Both the residences and these businesses had their right to exist, it was held, but not necessarily in close proximity to each other. Thus, the legal separation and isolation of land uses began, creating the foundations for many current zoning practices. ...
End of excerpt