The how-many-miles? hour

A report on Facebook recently, of a 41-minute, 49-second 4.0 mile run by my cousin Sara in Arkansas, inspired me to see how far I could walk in a mile. I guessed I might still be able to do 4.5 miles and wanted to test it. I'd walked 2.4 miles or so (I didn't record it) in 40 minutes yesterday on an elliptical machine at the local fitness center, knowing that I could do significantly more than that on "the open road."
    But how much more?
    On my wife's recommendation, I'd recently installed RunKeeper on my Droid. So, of course, I'd let it keep track of the time and the distance.
    So, at 7:26 a.m. today I set out. I hadn't turned on RunKeeper's audio commentary, so, as I approached home, after walking for what seemed almost an hour, I took out my Droid, turned it on, and entered the pin number, trying not to slow down. Fifty-two minutes and something.
     I continued past my house a couple of blocks and circled back. It was 58 minutes the next time I checked, and I held the Droid to be able to stop RunKeeper at precisely 1:00:01 hour.
    Four-point-16 miles. One-third mile less than the 4.5-mile target.
    Not too bad for an old guy.
    And I might be able to improve that some with practice.
    I could gain a couple of hundredths of a mile by turning on RunKeeper's audio....