So, Adam Heine's comment on condensers got me looking up different parts of the steam engine that make the mechanism operate at peak efficiency.
The ones he linked to, steam locomotive condensing apparatuses, were developed ostensibly to allow the London Underground to operate before the implementation of non-steam powered subway trains.
"A steam locomotive condensing apparatus differs in purpose from the usual closed cycle steam engine condenser, in that its function is primarily either to recover water, or to avoid excessive emissions to the atmosphere, rather than maintaining a vacuum to improve both efficiency and power. It takes the form of a series of pipes, valves and other ancillary equipment usually attached to an otherwise conventional steam locomotive. The apparatus takes the exhaust steam that would normally be lost up the funnel and routes it through a heat exchanger, into the normal water tanks. Installations vary depending on the purpose, design and the type of locomotive to which it is fitted."
Anyway, the whole reason for the title of this post is because, during the ensuing click-o-rama on steam engineering, I came across a reprint of an 1887 book on the mechanics of steam engines.
Long story short ... I bought it. It's exactly the kind of resource one needs to add verisimilitude to any explanation of steam engines. The text will also give me a way to make certain the hero of SON OF MAGIC knows what he's talking about when it comes to steam power, which is good because that MC is supposed to be a steam engineer.
So as you can see, in a roundabout way, it's Adam's fault that I bought that book. Yeah ... that's it.
P.S. The titles of the aforementioned songs for Steam's Limitations Part 2 and Part 3 are Metallica's "Fuel" and The Who's "Water."