gvasale, I have to comment on a couple of things....
"Shop Theory" 5th edition, by James Anderson and Earle E. Tatro, copyright 1934, has the following: " The father of the modern engine lathe was Henry Maudslay who first invented the slide rest." He also combined the slide rest with the lead screw with change gears. " This took place in the early 19th century and made the the lathe the most important machine in the industrial revolution, for without the lathe James Watt's steam engine would never have been built. Because it machined the parts of Watt's engine, it became known as the engine lathe."
No matter what your books say, steam engines were being made for over 100 years before machine tools came into common use. In fact, it was not until after the 1850's in the USA that machine tools were much used for engine manufacture.
Cylinders were bored (though probably the first Newcomen cylinders were not bored), but almost everything else before this time was made by hand, ie chipped and filed, plus some hand turning (ie lathe without slide rest).
I am not saying that engine lathes and planers were not in existance, they just weren't much used for steam engine (or other machinery) building, not in the US anyway, before the 1850's-60's.
Another thing...James Watts experiments in Glasgow (and elsewhere) resulted in his invention of the seperate condensor (1765), this alone dropped the fuel consumption of the atmospheric engine to about 1/4.
It was later that he came up with the double acting rotative engine (1783).
One book I have (see below) suggests that an engine lathe is one driven by mechanical power, and also is "automatic" in operation, ie having a powered slide rest.
A good book, though a bit of a slog, is Louis C. Hunter "Steam Power: A History of Industrial Power in the United States, 1780-1930".
