No vehicles with iron or steel knobs, spikes, knuckles, ridges or corrugations
on its wheels or tires and no vehicle, shovel, concrete mixer or other instrument
which travels on caterpillars shall be permitted on the highway unless conveyed
on a trailer or carrier or other means of protecting the highway.
The Police Department shall prevent congestion of traffic upon the highways,
and the drivers of all vehicles shall obey its orders, rules and regulations.