The main dial of the mechanism is about 4 inches across. Early medieval clocks were huge in comparison. The ability to produce such precision parts in the second century BC is amazing.

For me, it raises a big question re the whole received-wisdom "thinkers didn't tinker" model of ancient Greek civilization in its prime.

And it's a good example of how our knowledge of the past is in many important ways at least as fuzzy as our predictions of the future.

We don't -- we can't -- know how many of these (sorts of) things existed. But why aren't they mentioned in the historical record? There are at least two strong non-exclusive possibilities: (1) The historical record sucks, (2) it was some sort of elite intelligentsia supertech -- perhaps akin to a priestly ENIGMA machine and as closely guarded.

Our knowledge remains fuzzy, even as the design of the apparatus itself swims ever more clearly into our ken.

I wonder what Lee Harris makes of it?

Thanks Joe and Nort for sharing. I think the quote is from Ambrose Beirce:

There is nothing new under the sun but there are lots of old things we don't know.

it was some sort of elite intelligentsia supertech -- perhaps akin to a priestly ENIGMA machine and as closely guarded.

A clue to its nature is the fact that it's so compact. Medieval devices of this nature were mostly built to stay in one place, and size was no object. Gears are widely spaced on large, open frames - easier to build, easier to repair, easier to explain how it works to the rich patron who paid for it.

Why did it have to be so small? It's as if it had to be easily portable, which is very strange. It would have made an overly-extravagant navigation device, and too valuable to risk by having it constantly at sea.

The Antikythera Mechanism first came to popular light in a June 1959 article in Scientific American:

Text to display

Even then it was believed to be an astronomical analog computer.

Oops, read the instructions too closely"

Antikythera Article

Why did it have to be so small?

A toy perhaps. An item of personal or close amusement to take and show. An item of vanity for which time was cheap, but materials were dear.

If so, what else was there?

It's astonishingly elaborate for a toy. When I think "Greek toy" I think Heron's steam spinner, not an analog computer that does moon phases and sothic and saros (eclipse) computations.

The teeth are reported to be triangular, not the more sophisticated involute shape. This is good for my digestion -- if they were involute-shaped I'd be thinking seriously (and dispeptically) about time travelers.

{...Cool gear basics link here...}

The best explanation I've heard for it being found in a shipwreck was that it had been looted from its rightful place by Romans.

Naturally, Wikipedia weighs in...

While a century of research is finally answering the question of what the mechanism did, we are actually no nearer to answering the question of what it was for.

True dat.

This definitely proves that the Romans were first-class looters. They didn't just steal the gold and the pornographic tapestries.

I'm awed. Amazing.

That article from SciAm that Captain Ned pointed to is full of other interesting info.

All the metal parts of the machine seem to have been cut from a single sheet of low-tin bronze about two millimeters thick; no parts were cast or made of another metal. There are indications that the maker may have used a sheet made much earlier–uniform metal plate of good quality was probably rare and expensive. All the gear wheels have been made with teeth of just the same angle (60 degrees) and size, so that any wheel could mesh with any other. There are signs that the machine was repaired at least twice; a spoke of the driving wheel has been mended, and a broken tooth in a small wheel has been replaced. This indicates that the machine actually worked. [Emphasis mine]

So, yes, this thing was not mass-produced by any means. Very labor intensive, as PD Shaw indicates. Yet it also seems clear that it was an apex design that must have been the outcome of a lot of earlier trials; and that it's the only one we've ever seen does not mean that more didn't exist elsewhere.

Note that in 1955-'59 they hadn't been able to identify the moon phase structure that rides around the front, only the three main display plates. But they did decode a lot of the inscriptions that appear to constitute the manual of operation.

So who needed to travel and to do astrological - astronomical figuring wherever he went? Were there "CC Rider" event planners in BCE Greece? Hmm.

Some kind of astrologe had their own "laptop" or iphone, so he could travel around keeping the business open.

Theoretical knowledge was well developed then, although practical applications on work were hindered by slavery. In fact, the calendar we use today, 365.25 days, was set by Caius Iulius 2000 years ago, and worked without an adjustement for 1500, which is remarkable indeed.

BTW, don't tell the clients the ship sank.

Imagined call to client: "It's not lost in a sunken wreck, sir... it's... in superdisplaced storage!"

Joe added a link in the entry at top, crediting Mike Daley, to a very nice plain website (text + static pictures) with lots of great details.

This quote from there rang so, I almost got persistent tinnitus from reading it:

Reading the research report’s description of its analysis of the dials and inscriptions on the device is almost like reading an alternate history novel (a sequel to a book by L. Sprague de Camp, say, The Glory that Was), where science took off in antiquity and all this arcane technology that results is accompanied by an impressive Ancient Greek technical vocabulary… except that this is our timeline.

Yeah. Trippy, man.