Nelson Bell Boat Buoy

Today we went shopping for a new starter motor in Preston in Lancashire and snapped this while we waited at traffic lights. 
This is what I found out about it:

The two ‘Nelson’ safe water landfall buoys were originally moored eight miles out to sea off the coast of Lytham, where the Ribble Estuary meets the Irish Sea. Today, however, they stand at two of the main entrances to Riversway, a modern development comprising a marina and a range of industrial, commercial and residential buildings. Today the Nelson buoys mark the original course of the river Ribble, which was diverted in the 19thCentury to enable the construction of the docks.
In 1890, in preparation for the opening of the new dock in 1892, Preston Corporation purchased two Bell Boat Buoys from the Irish Lights Commissioners for marking the Nelson "Safe Water" mooring at the entrance to the estuary and the Penfold channel. The lights on these units were powered by acetylene gas and the bells were rung by wave motion.