Would You Vote Favourably On A Sewer Gas Destructor Lamp? (Victorian Infastructure)
Somewhat similar to the 'Drain-waste-vent systems' (also known as 'stink pipes') that people vote favourably on, only far rarer. As the Wikipedia article notes, there is only one 'Sewer Gas Destructor Lamp' left in the whole of London. Each one appears unique in its design, like the stink pipes.
I had a stink pipe in a small village accepted just the other day actually. Here is the 'Sewer Gas Destructor Lamp' on Google Street View: