On 06/03/2018 11:09, Martin Brown wrote:


The old technique was a sort of pole which the old guy who checked
such things put his ear to and behaved pretty much like a
stethoscope. You can hear leaks and free running water underground
with such a device.

We had a water company employee going around with a stick listening to
the stop taps a couple of years ago. It was 3 in the morning.