Well, this explains any number of things.
1. The real reason they are called pointers.
2. Why fire hydrants are round (as in 360 degrees)
3. How dogs find their way home from 1000s of miles away.
4. Why every dog in the neighborhood likes my mailbox (the street runs due north)
http://washington.cbslocal.com/2014/...agnetic-field/
But no one ever cleaned up after a compass.
We are currently dogless. Those of you who have such a beast may want to make the observation.