Oldest operational computer

[Chuck Guzis]

I think that many people are overlooking the matter of available 
techniques and materials in 1900 when supposing a computer operating 
in the Kops range was possible.

No printed-circuitry; indeed, the mode of much electronic 
construction was busbar-type wiring on a varnished piece of wood.  I 
don't know when enameled "magnet wire" came into production, but the 
standard for magnet wire for a long time was silk covering.  Hookup 
wire may have been cotton or cambric, with gutta-percha for 
insulation.

Resistors of any precision would likely have been wirewound.

Does one need audions for amplification?  Consider early telegraph 
repeaters or even chart recorders (running on a wind-up spring and 
recording microvolts).  Even audio amplification could be achieved 
using compressed air.

At the time, pneumatics were at a pretty high stage of development.  
Consider the workings of a player piano or pipe organ.

But I think the technology that would have been selected in 1900 
would have been mechanical or electro-mechanical.  Consider, for 
example, the work of Leonardo Torres Quevedo.

Cheers,
Chuck