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Railway staff in Indonesia have started hanging concrete balls above

train tracks to try to prevent commuters from riding on carriage roofs.

I challenge any writer of a Daily Paradox to resist this one.

The problem, of course, is serious. Indonesians, and others, enjoy a free ride on top of a railway carriage any time. Apart from the economic benefits there is the relatively fresh air, the cool slipstream ruffling the hair, a sense of adventure found in few other places.

And the views! Short of Nat Geo Wild where else can you be part of a fast-moving safari, safely above any dangerous creepy-crawlies but very much part of the environment. It must be exhilarating, challenging, scary as a bungee jump, satisfying as any armchair theatre. Alas, it is not risk-free. Indeed, many lives are lost in the search for the adventure perk that is about to go.

It is not as though the authorities have been idle. Several attempts have been made to discourage the practice of mounting the carriages. Water canon, beloved of the French authorities in clearing protesters away from Place de la Concorde; grease with its successful record discouraging pigeons from gaining a ledge about Nelson’s head; red paint to identify infringers of the Railway Company’s regulations; all have been tried to no avail.

The system has its own built-in corrective technique – electrocution by the wires supplying power to the vehicle. Even the most authoritarian enthusiast would find this a bit drastic especially as most contacts with a live wire prove fatal. ‘Better,’ it has been decided, ‘to deter rather than to decease’.

So bring on the grapefruit-sized concrete balls.

Aficionados of the Dad’s Army comedy series will recall the enthusiastic promotion by the Sergeant for the use of bayonets applied rectally and accompanied by his immortal phrase ‘”they don’t like it up them”. Concrete balls will not, mercifully, have the same effect as bayonets but they can deliver a sharp smack to the head, and likely one that will never be forgotten. Or, perhaps, remembered.

And so an era of top-of-the-carriage riding is coming to an end. Mourned by those who will be deprived of free personal mobility, it will, I am sure, be welcomed by the railway staff as a preferable alternative to actions with more dire consequences. Personally I shall regard it as one more freedom ruthlessly removed by authority determined to make life risk and adventure free.

But then I have never got to the top of the carriage, so I am hardly qualified to say.