Oldest operational computer

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