Difference engine
today 184 years ago Charles Babbage proposed his difference engine to the Royal astronomic society.
(listed on Wikipedia’s frontpage today). Babbage died before he could finish his device, but the the London Science Museum constructed a working Difference Engine ( the no. 2 design) from Babbages plans. The side shows a wood cut from a part of the difference engine 1, that was build 1833 (left image from here). When he did not succeed in building his difference engines Babbage strived for more: the analytical engine: a disign that if it ever had been realized would have been a mechanic Turing machine. The worlds first computer program was a program for the analytical engine to compute Bernoulli numbers by Ada Lovelace.