About that Babbage engine ...

[Dr Pervez Hoodbhoy]

What's the earliest date to have a functioning one built, what are the uses it could be put to, and how would it affect science and technology? I will quite frankly admit that, except for the obvious cryptological uses, I have no clue.

[Max Sinister]

Well, you could use it for calculations, frex of logarithms. (Which was the main reason why Babbage invented the machine first - he was fed up with calculating stuff like that over and over again.)

[Justin Pickard]

Earliest possible build? The first engine was concieved of by J. H. Mueller, an army engineer from Hesse, in 1786.

For Babbage's difference engine, we're probably looking at the 1850s, maybe (although it might be pushing it) even in time for the Great Exhibition in 1851.

Here are the obvious uses that I can think of -

(1) Social statistics (censuses, identification and the like)

- Babbage's distaste for commoners and the lower class could have made this take a decidedly Social Darwinist turn.

(2) Public health and epidemeology (tracing outbreaks of disease)
(3) Economics and econometrics
(4) Astronomical tables
(5) Train timetables

[Tielhard]

Earliest possible build? Well sometime after we have CAD, high tolerance machining and a modern concept of goodness of fits. Some time between 1965 and 1975.

[Justin Pickard]

Earliest possible build? Well sometime after we have CAD, high tolerance machining and a modern concept of goodness of fits. Some time between 1965 and 1975.

It doesn't necessarily have to be the Analytical Engine. The Difference Engine would have perfectly possible at the time.

Per Georg Scheutz (http://en.wikipedia.org/wiki/Per_Georg_Scheutz), a Swede, built several difference engines from 1855 onwards; one was sold to the British government in 1859.

[jolo]

If Greece had not been destroyed by internal fighting and Roman conquest, it might have continued it's technological and intellectual blossoming. They were already able to build complex astronomical calculators at their peek, they could easily have produced clocks, calculators, and so on.

The 0 would have to be invented sometime, but contact to India already existed (even before Alexander), so that's not too difficult to imagine within the next few centuries.

Imagine Greece on 17th century level at about 0 A. D., and surrounding places adopting nearly the same levels due to normal spread of technology and competitiveness. From then on, everything could easily run at the same speed as it did in northern Europe 1700 years later, which means a difference engine at about the year 200.