Re: USA 250-256 [Spoiler Alert: Engineering/Thermodynamics Content]

My intent was not for this discussion to go this way, but I cannot say that it has not been interesting just the same. It is not NG but in my part of the woods, the Crowell and Spencer Lumber Co, and the Red River and Gulf RR, which it owned, had a 50-60 mile daily haul. Between 1919 and 1923, the companies ordered 4 virtually identical 4-6-0's from Baldwin. I say virtually identical, because the first two, which were for the lumber company's main line 50 mile daily log haul were superheated and built in 1919 and 1920. The third was built in 1922, for the railroad as their primary locomotive, and despite a number of real improvements, it was built as a saturated engine with balanced slide valves to save on maintainence costs. In less than 10 months, the railroad went back to Baldwin and ordered the fourth engine, and it again was superheated. The fuel and water savings even on the 50-60 mile haul, was much more than the maintainence costs of superheating and the single saturated engine was relegated to the shorter hauls of like 12 miles rather than the longer runs.