One of the worst offenders against civic beauty and good taste is the flaming billboard which stares from every vacant lot into the faces of the passers-by. For the most part billboards serve no very useful purpose. The advertising which they carry ought to be given to the newspapers, which reach a far wider circle of people and are actively engaged in promoting the best interests of the community. These billboards often mar what would otherwise be an attractive avenue or landscape.[86] The cities of Continental Europe virtually prohibit them altogether. It is not possible to do that in the United States because of constitutional restrictions which protect private property; but billboards can be restricted by law and some American cities have adopted the policy of so restricting them.[87] It is also possible to levy taxes upon them and thus to make billboard advertising less profitable. =The Municipal Utilities.=—In addition to streets, parks, and public buildings every city maintains various other physical utilities. These include, in some cases, bridges, docks, markets, ferries, and so on. More important, however, are the so-called _utilities_, the water supply and the sewerage system. Both of these are intimately connected with the public health and can better be dealt with when we come to that general topic. Some cities own and operate their lighting plants, and in a few cases their street railways. But lighting and transportation are still, for the most part, in private hands and they present problems of such importance that they need a chapter to themselves (see pp. 474-481). [Sidenote: Beginning of the police system.] =Police Protection.=—The practice of maintaining in cities a body of professional, uniformed policemen who give their full time to the work of preserving law and order is less than a hundred years old. Until well into the nineteenth century the work of protecting life and property was performed by untrained constables and watchmen (in England and America), or by squads of soldiers (in most of the larger cities of Continental Europe).[88] London, in 1829, was the first city to install a regular police force, and this action met with great popular opposition. It was regarded as a step in the direction of tyranny.[89] But regular policemen proved to be so much better, as guardians of law and order, than the untrained constable in citizen’s clothes, that other cities followed the example of London and eventually the system was established in the United States, the first city to adopt the new plan being New York. Although New York was at that time a city of over 300,000 population the work of policing was largely performed by elective constables and by citizen watchmen until 1844. [Sidenote: Police organization today.]