The Glamorgan canal used to wend its way from Merthyr Tydfil through the centre of Cardiff to the docks. At first it was a waterway with mysteries that had to be solved. It vanished just before Queen Street in the centre of the city and emerged the other side.

Barges were pulled by big draught horses being led along the tow path, which were detached before Queen Street and led to the towpath on the other side. We realised there must be a tunnel under the street, but how did the barges keep moving while in the tunnel?

It was a question that perplexed me for years while still too young to be allowed on to a potentially dangerous canal towpath without an adult. But then came a day when I ventured there with my cousin, Peter, and found the answer: there were heavy, and rusty, chains embedded into the walls of the tunnel and the bargees simply pulled the barge along.

The canal became a part of young life in the late 1930s and early 1940s. My father, Thomas Arthur 'Doc' Williams (pictured above), was a strong swimmer as a young man. He had received a Royal Humane Society certificate for saving the lives of two children who fallen into the canal: it vanished one day from my mother's home when she was living alone and very elderly, to the great regret of my brother and myself.

Cousin Peter used the canal for pocket money, coaxing American servicemen during the war to throw silver coins into the canal from a bridge across the road from Cardiff castle, which he would retrieve, always emerging from the water with a coin in his mouth. Did the relentless diving and swimming in cold water eventually lead to the bad arthritis that affected him in later life?

We used to swim in it in the summer, although it was full of urban deritrus, and black with coal dust. There were patches of warm and cold water. Sometimes we were so cold coming out of the water that we would light a fire for warmth.

We also swam at timber floats off upper Bute Street, not far from the canal, but there was greater danger, with big pieces of timber lashed together like rafts; we worried we would find ourselves trapped under the timber and unable to find a way out.

Sometimes we would lash timber together ourselves and go cruising precariously down the canal, like latter-day Huckleberry Finns. It was not easy as the logs were unstable but we came to no mishap until the day that a friend, Howard Knott, fell in.

He and all his clothes were soaking wet and he was afraid of his father, a strict disciplinarian. He had had firm instructions­ not to go near the canal. We found old newspapers, cardboard and wood - there was always rubbish along the canal bank - and lit a fire under a bridge near the Hayes.

Howard took off his clothes and stood shivering­ while we tried to dry them. Eventually he had to put them on, still damp. We told him they would be dry by the time he got home. He walked into his house, uncertainly, but feeling he and his clothes showed no evidence of the wetting. He said his father took one look at him and said: "You fell into the canal."

Glyn Williams - Perth, Australia - April 2007