4 ms·
My guess would be that (many, most) manhole covers are round because it is the obvious shape for most lids. There are so many poorly designed urban objects that
by diego 19y ago
My guess would be that (many, most) manhole covers are round because it is the obvious shape for most lids. There are so many poorly designed urban objects that I tend to believe that the feature of not falling into the hole was a lucky accident.
Think of stop signs, for example. It would be really easy to have a different shape/color for four-way stops, but at least in the US all they do is add "four way" to the sign in an inconsistent way.
- LogicHoleFlaw 19y agoI think having multiple shapes for stop signs would be a terrible idea. The red octagon is an international standard. Messing with it is just asking for trouble. The "4-way" signs are just an aid to drivers, to indicate what behavior they can expect from other drivers. They're not required, and no replacement for plain old good judgment.