Phrases in the Green Mile by Stephen King

I am trying to find out the meaning/origin of the following phrases from Stephen King's book the Green Mile:

dead run
in a walk
riding the rods
lickety-larrup
killing bottle

a "dead run" is an all-out full speed run

And if you run at a dead run and get a big enough lead in a race, sometimes you can approach the finish line and not even have to run to seal the victory: you win in a walk.

Riding the rods (or rails) is a means of transportation that hoboes used (and may still use, as far as I know) riding on the undercarriage of rail cars. It is, of course, dangerous and illegal... but thrifty.