On 9/27/24 7:02 AM, Andy Walker wrote:
On 27/09/2024 07:52, Lawrence D'Oliveiro wrote:
[...] Imagine
that Charles Babbage hadn’t completely failed at building his Analytical
Engine. (Only it was called the “Difference Engine”, for some inexplicable
reason.)
The Difference Engine was a completely different project. It was
called the Difference Engine because it was meant to calculate differences*,
which were the principal tools in numerical mathematics for the calculation
of values of functions [sine, cosine, sqrt, log, ...]. In the days before
computers, tables of such values were an essential part of the engineer's
[or physicist's or statistician's] toolkit and was what mathematicians often
spent their entire careers providing and checking. It was tedious work, so
was ripe for automation.
Babbage is remembered today for little more than these projects, but
he did much more than that. His Wiki article is worth reading, if only to
learn the breadth of his interests and contributions.
Babbage really was a gifted engineer and maths guy,
he had enough rep to get the govt to front him rather
a lot of money to build the difference engine.
Apparently costs-analysis was NOT one of his best
skills alas. The machine is devilishly complicated
and was at the cutting edge of mechanical techniques
and precision at that time.
I think some MIT people finally *built* one, or a
substantial part of one. I've seen a vid, all the
brass clockwork is hypnotic to watch.
I'd say his greatest accomplishment was establishing
once and for all that any math/logic can be done by
machine, no 'magic' in a human brain required. The
mid 1800s were when they could finally whisk away
all the pixies and 'principles of' and 'essences'
and made 'natural philosophy' into real science.
Lada Ada does indeed have a rep for being a pain
in the ass and a relentless egotist/self-promoter.
However she DID immediately grasp the concepts
behind the Analytical Engine (even wrote a big
promo for it - there's a French text on the net)
and DID see it's more esoteric uses whilst Babbage
was mostly obsessed with doing boring math algos.
Ah, a translation she did of that 'promo' for
British consumption :
https://old.maa.org/press/periodicals/convergence/mathematical-treasure-ada-lovelaces-notes-on-the-analytic-engine Alas the AE was even more complex than the DE plus
Babbage kept revising and revising the gearworks
and thus never arrived at what you'd even call a
"final design", much less an actual device. The
reasoning of what it NEEDED to do was perfectly
sound however - as important as an actual product.
It WAS (or would have been) a "general-purpose
computer" ... a i8008 in shiny brass.
Poor bastard was born about 50 years too soon - if
he'd ever seen a triode tube ...
There WAS some Russian ex-pat building digital logic
circuits with trides/'valves' in the 1910s as I
recall - the U *THREW MOST OF IT AWAY* after he retired,
only a few assemblies survived (looked like 8 or 10
bit adders).
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