Exactly! Part III or IV will end up talking about boring techniques of the 1650s (long before the famous John Wilkinson methods), but that is precisely the thin

Exactly! Part III or IV will end up talking about boring techniques of the 1650s (long before the famous John Wilkinson methods), but that is precisely the thing with Savery engines - and indeed with Newcomen engines, which worked with pistons long before Wilkinson too!