Bristol - Corn Exchange

The lesson follows.

The clock was first installed in 1822. A second minute hand was later added to show the time in London as well as the local time in Bristol; the black minute hand shows Greenwich Mean Time and the red minute hand shows Bristol time. This became necessary following the arrival of the railways, which required a standardised time for timetabling around the country, known as railway time; Bristol officially adopted railway time on 14 September 1852. The city is 2º 35' west of Greenwich, so when it is noon in Bristol by old local time, it is just after 12:10 p.m. in London by standard time.

So, now you know.