Before our house and the neighbouring house were built, the owners of the land laid 2 water pipes from the water meters and led them up the hill. They are 32mm blue alkathene and identical. The other house was built first and they connected to pipe A. When we built our house, we chose to put the house at the bottom of the hill (nearer the sea) so the builders cut our water pipe (pipe B), put a 90 degree elbow on it and connected the house to it. So there remains a length of unused pipe that's open ended at the bottom of the hill (and we've found it) and it goes goodness knows where up the hill.
With me so far?
We have a croft with sheep, ducks and hens and a larger garden than we envisaged, so thought it would be good to join one of these schemes where foreign students come over for a week or a month and work a few hours a day but get free food/accommodation and get "cultural" stuff. We didn't want them living in the house, so have bought a decent caravan and plonked it a little distance away from the house. And the water pipes run next to it.
So we've dug down to these 2 identical pipes, one supplying our neighbour (A) and full of water; and (B) empty of water (it's on a slope, remember). It's just a question of joining the caravan up to the empty one and then T-ing the open end down at the bottom of the hill to our pipe.
The 2 pipes are identical and next to each other. A 1mm drill bit will prove which is which, but I don't want to have to repair pipe B if I choose wrong. Science come to my help and I tapped each one with a stick. One is most definitely higher pitched than the other. I make my decision which is empty and which is full, but Mrs T is convinced I am wrong.
I drill the hole. Which one did I choose as the empty one, the high pitched or the low? Did I get lucky, punk? What do you think, and why? And was there any better way of finding the empty one?