Irwell bicycles were built by the Manchester Cycle Manufacturing Corporation Limited.
One very original example remains: even with original head transfer!
The factory was housed at Clayton Lane in Manchester, in earlier years they built the lever-driven Clavinger high wheel safety, in later years the Belsize, with interesting hubs. In the V-CC digital catalogue, which is open for everyone, you can see the 1896 Belsize catalogue.
The owner of this Irwell is making a nice website about the restoration and the story behind the bicycle: what more can I add?
(click picture for the link)