I ran across a couple of these before, these are great! The kid on the dirt street with the boots on, in Hooch's first set, I remember reading that photo was from 1920, somewhere in Texas, Austin maybe, and he ran his own messenger service. I believe that photo was taken in the "red light" district, where he would relay messages...
"William Martin, champion six-day bicycle rider of the world, full-length portrait, facing left, on bicycle"
a GREAT photo resource if the Library of congress, go here: http://lcweb2.loc.gov/pp/pphome.html
type in what you want to look for, like "bicycle", the bonus? most of these photos, you can BUY copies of. COOL!