*One of the many Gothic aspects of the Difference Engine was that the device, which was never successfully built, was never quite entirely dead, either. Babbage's youngest son, a career military officer, could never let the project go. He kept dragging the revenant out of the South Kensington museum to tinker with it and show it off to the scientific gentry. Effectively dead as a machine, it nevertheless percolated through history as long as human beings existed who had ever laid hands on it.
*And, of course, now there are two of them, full-scale and good to go, plus restored pieces of the calculating machinery on show here and there.
*The dry, apologetic writings of the younger Babbage are full of haunting echoes of the future.
http://www.fourmilab.ch/babbage/hpb1910.html
http://www.fourmilab.ch/babbage/hpb.html
He called this arrangement “the engine eating its own tail.” (((feedback, cybernetics)))
It is to be noted that the engine is designed for analytical purposes, and it would be like using the steam hammer to crush the nut, to use the Analytical Engine to solve common sums in arithmetic. (((hacker elitism)))
Now it may happen in addition that two or more numbers being added together, there may not be room at the top of the column for the left hand figure of the result. This would usually happen from an oversight in preparing or arranging the cards when space should be left; but it might so happen that the calculation led, as mathematical problems sometimes do, through infinity. In either case a bell would be rung and the engine stopped (((bug)))
This principle of “Chain” is used also to govern the engine in those cases where the mathematician himself is not able to say beforehand what may happen, and what course is to be pursued, but has to let it depend on the intermediate result of the calculation arrived at. (((generative art))) He may wish to shape it in different ways according as one or several events may occur, and “Chain” gives him the power to do it mechanically. By this contrivance machines to play simple games of skill such as “tit tat too” have been designed. (((computer games)))
It could follow the processes of the mathematician be they tentative or direct, wherever he could show the way to any number of numerical results. It is only a question of cards and time. Fabrics have been woven requiring several thousand cards. I possess one made by the aid of over twenty thousand cards, and there is no reason why an equal number of cards should not be used if necessary, in an Analytical Engine for the purposes of the mathematician. (((software libraries)))
63. There exist over two hundred drawings, in full detail, to scale, of the engine and its parts. These were beautifully executed by a highly skilled draughtsman and were very costly. (((The pathos must have truly been hard to bear.)))
I see no hope of any Analytical Engine, however useful it might be, bringing any profit to its constructor, and beyond the preparation of this Paper, and the publication of the volume I have mentioned as shortly to follow, there is little or no temptation to do more. Those who wish for such an engine would, I think, give it a helping hand if they could show what pecuniary benefit it would bring. The History of Babbage's Calculating Machines is sufficient to damp the ardour of a dozen enthusiasts.
(((The Engines are still prestigious loss-leader gizmos, and they still live in museums or in the parlor of a geeky zillionaire. Running one of these contraptions would be no picnic. But you know something? They're not dead. They're certainly much more famous now than they were in the long twilight around 1910, and their fame, if anything, seems to be increasing. If somebody had told Ada Lovelace that she would be best-known to futurity for associating with an unbuilt brass gizmo, she would have been stunned.)))
Among the things which came to me in his will there was a large number of pieces fitted and ready for the difference engine; but many of the frame plates had been cut up and used by my father for experimental work. I thought to replace them and put together what existed. I began by having plates made to complete the framework as originally designed, and to put in their places the pieces, some completely finished and others less so. I also contrived a new driving gear which answered perfectly, but I found the expenses heavy and the utility doubtful, and about 1879, not knowing what to do with it, I sent the whole (excepting five or six small pieces sent to different places) to the melting-pot. (((Ouch.)))
About that time I heard that Mr. Wilkinson, a nephew and successor of Clement, had broken up his workshop and melted up what remained there of the unfinished pieces of the difference engine. (((Ugh.))) Had I known this in time I might have kept what I had, for I still hold to the opinion expressed in Babbage's Calculating Engine, published in 1889, that the calculating part of the difference engine might have been completed, at the time the Government gave it up, for, say, £500.
((("Pi" being multiplied and printed by a Difference Engine in 1910:)))
(((Just a simple matter of beautifully hand-drawing thousands of parts, and then
deciding how all the hardware subunits fit together, which, in the case of the Analytical
Engine, no one has ever finally decided. You'd have to reinvent an Analytical Engine
rather than duplicate one as a nifty counter-historical prank, and that would be
quite a feat.)))
