Shrewsbury hopper

 

If you just look up, and carefully, you'll see plenty of loggerheads, even in the most unlikely places.
This set is on the hopper of a rain downpipe at the Old Market Hall in Shrewsbury town centre.

The OMH building rests on stilts, so to speak, with an open space beneath it that once served as a public market where the the certain stalls within it kept out of the rain.

The first floor area (which you glimpse here) would have been an civic-administrative space, which is why there are loggerheads all over the OMH.  Nowadays, the first floor at the OMH is a cafe and small independent cinema. 

I guess that the loggerheads device on this hopper is what would you'd call an example of civic pride in action.

Which firm would have erected these?