The precision machine tooling that produced these intricate machines could not have been achieved in an earlier age.  Babbage’s inventions were born of the advances in technology that accompanied the Industrial Revolution.  The Difference Engine was never fully built.  Babbage drew up the blueprints for it while still an undergrad at Cambridge University in England.  But while it was in process of being manufactured, he got a better idea and left this work unfinished in favor of the Analytical Engine illustrated on the next slide.  The Analytical Engine was eventually built completely in the latter half of the 19th century, by Georg and Edvard Schuetz as per Babbage’s blueprints.  Film footage exists of the machine in operation, and it is truly a sight to behold, a testament not only to Babbage’s genius, but also to the manufacturing prowess of the age.