Local governments in the Philippines have been vested with conventional urban planning powers for many years. During the 1920's, the Revised Administrative Code was amended to provide for the preparation by the director of public works of general plans for adoption by municipal and provincial governments. Although the term "general plan" was not defined, it may be inferred that its function was to lay out and locate public buildings, parks, etc. and perhaps, to lay out major land use areas for further action in the form of a zoning map and ordinance. At about the same time, a number of local governments, without benefit of any zoning enabling act, enacted rudimentary zoning ordinances restricting the location of certain noxious industries. Those ordinances were sustained by the Supreme Court, which found a sufficient source of authority in the police power granted to local governments under clauses covering heatth, sanitation, the abatement of nuisances, and the general welfare.