I was always under the belief that the term "Hi-rail" came from the use of tubular track (rails are much taller than those on scale track), and that a Hi-rail layout was one that used tubular track with added ties, ballast and somewhat realistic scenery - much like Warrenville. This is true but there is a history to the term "Hi-rail"
I was just reading a book from 1953 wherein a writer states that the term started with a much different meaning. It seems that during WW I, Army Railroad engineers were called "Rails". When greeted, people would say "Hi, Rail". It seems that years after the war one of these "Rails" and his sons wanted to bridge the divide between scale train and toy train layouts and went to a hobby shop with their list of tubular track and more realistic scenery items.
As this hybrid of styles became popular (mostly due to its ease of construction compared with full scale), the term "Hi, Rail" evolved into "Hi-rail".
I learn somethin' new every day!
Has anybody here ever heard this story before?