T W Freeman “The town and district of Carrick-on-Shannon, Co Leitrim” in Irish Geography (Bulletin of the Geographical Society of Ireland) Vol II No 1 1949:
There is no mill in use now, though flour is sent from Rank’s in Limerick by barge to Carrick, but no farther. Before the 1939–1945 war general cargo was also brought to the town by barges which could convey 50 tons of coal; other goods included timber and galvanised iron for builders. At present, stout is the only commodity brought by barge to the solidly-built stone warehouse of the early nineteenth century, whence it is distributed for some twenty miles in every direction.
Irish waterways history 