I recall reading about Babbage's work many years
ago and it was the
opinion of the author (I don't recall the source, sorry) that AE was
basically unbuildable using 19th century materials and methods. The
reason to the best of my recollection appeared not to be the scale,
but rather simple mechanical considerations; that is, frictional
losses, strength of materials, etc.
Does this view still hold any merit?
It is also "well known" that the capability of building something on the
order of the Antikytheran device did not exist at the time that the
Antikytheran device was built. "They didn't even have gear teeth shaped
like that until a thousand years later"