magnets

I was at home this weekend, bored out of my mind, so I decided to do something physics related. Everyone knows the bigger the magnet, the bigger the magnetic field. So I found my humagangous magnet and had some fun. My dog was lying down and there was a nail on the other side of him. I ran to him and put the magnet by his stomach, the nail jumped to the magnet. Since magnetic fields have forces far beyond what they actually reach, I wanted to see if forces could go through objects too, like through a dog. So i put the nail two inches from his stomach and the magnet on his back. It didn't work, it wasn't strong enough. Which I realized later was a good thing because the nail would have stabbed my dog.