The story of MoPac ...

So after years of living up here and asking tens of people why Loop 1 is called MoPac (and why it's called a loop when it doesn't, you know, loop) and no one knowing why, I finally found out by asking Darien, the bastion of knowledge that he is. And the answer makes so much sense. Apparently, MoPac stands for the Missouri Pacific railway that goes through most of Loop 1. Finally, an answer. I can rest easy now. Well, easier, until I find out why its called a loop when it's more of a chord. Right?