History is longer than we thought

See: World's First Computer

http://link.springer.com/article/10.1007/s00407-014-0145-5
and
http://www.huffingtonpost.com/2014/12/02/antikythera-mechanism-older-than-thought_n_6254146.html?utm_hp_ref=science

It was well built.  Somebody had built prototypes.