Tanks

Out walking today and The Boss spotted this.
I wondered what it was, sitting up on the ridge like that and he said it was a water tank. I thought it was a silly place to have one of those and he said it was so the farm dogs could have a drink, if they needed to.
After checking it out with my dPad (iPad with K9 Pawboard) I calculate that it holds enough water to allow me to personalise 27,673 spots so I wonder if The Boss is pulling my lead about this.
I gave him a hard look and he started,
“Mark my words…….”
But I simply couldn’t reach.

Oh go on… look