Venting about the Tube

A brainy start to the day.  Well if your name was James Henry Greathead luckily for us it was.  He designed the tunnelling shield, the machine that drove the second only tunnel under the Thames that pops us up at Tower Hill.
It was not until more than a century later that the man was honoured with this statue.  I'm sure he'd be delighted that the plinth he stands upon encases the ventilation shaft for the tube line that passes underground here.