Dave Gathman wondered how the mail works:
Every time I dropped a letter into a mailbox (usually a bill payment that had to get there fast, or my interest rate would shoot up to 33 percent), questions lingered. Would the letter get there just as fast if I mail it at the corner "blue box" as it would if I mailed it at the post office? Would a letter mailed in the little Hampshire post office arrive as soon as one mailed in downtown Elgin? Is it true, as someone once told my mother-in-law, that "mail doesn't move on weekends?"Read all about it:
So we did some experimenting.
Secrets of the Post Office (Elgin Courier News)