On 25 Sep, 19:05, "John" wrote:

Our lads (BT) use a plastic carrier bag rather than a ball - doesn't half
fly down the duct *)

I still remember the first time I saw a "duct motor" in action, years
ago as a damp-lugged BT apprentice. Damned funny things to watch
throbbing away on a concrete yard, let alone when it's a crowd of
teenagers and the odd mucky-minded Essex (Suffolk, near enough) girl.

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