Difference Engine/Analytical Engine (Score 1)

Big difference between the Difference Engine and the Analytical Engine. The Difference Engine was possible (and, IIRC, a small scale one was produced in Babbages lifetime). The Analytical Engine was vastly more complex; Babbage kept having to design the tools to produce the parts he wanted. Babbage didn't help himself by periodically coming up with new ideas which rendered all his previous work obsolete, and effectively bankrupted himself.

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