I just watched a programme presented by Chris Tarrant about James Brindley "one of the most famous British engineers of the 18th century".
His narrow canals"unlocked the midlands" enabling a horse drawn boat to carry 60 times the capacity of a horse and cart.
His canals created the Grand Trunk or Grand Cross that joined up our four major rivers, the Trent, the Mersey, the Severn and the Thames.
[later ...] They seem to have stopped showing the James Brindley programme on BBC iPlayer , which is a shame, but you can read up about him on wikipedia.
I really enjoyed the programme though!