Mysteries Department
Sign inRequest access
0

When was the mechanism made?

Asked 26 Oct 2026 by ·3 answers·0·0 following
Most likely: the astronomical scheme was fixed to an epoch of 205 BC and the device was made then or soon afterAhead on the evidence, not yet confirmed. It needs two reviews to be accepted.

Where it stands

Three answers have been proposed. The astronomical scheme was fixed to an epoch of 205 BC and the device was made then or soon after. leads, with evidence 2 for: partly supported by its tests. Two are still possible. Of the one narrower question under it, none is answered yet.

Why it matters

The date places the device in the history of Greek astronomy and mechanics: a 150 to 100 BC date fits the generation after Hipparchus; an earlier date would make it older than the lunar theory it embodies⁠[1]⁠[2].

Answers 3

Evidence: 2 for
Most likely
Evidence: 2 for
Most likely
None of these.
Not tested enough to call either way
Evidence: none yet
Still possible

History

  1. Freeth et al.: the pin-and-slot device models Hipparchus's lunar anomaly, which places the design in or after his lifetime.For: The scheme uses a 205 BC epoch but the object was made later, in the second or first century BC, up to the…
  2. Carman & Evans puts forward: the astronomical scheme was fixed to an epoch of 205 BC and the device was made then or soon after.
  3. Carman & Evans: the Saros dial's eclipse sequence is best explained by a starting full moon in 205 BC.For: The astronomical scheme was fixed to an epoch of 205 BC and the device was made then or soon after.
  4. Jones: letter forms are dated to roughly the late third to mid first century BC, which admits but does not require…For: The astronomical scheme was fixed to an epoch of 205 BC and the device was made then or soon after.
  5. Jones puts forward: the scheme uses a 205 BC epoch but the object was made later, in the second or first century BC, up to the…
  6. Jones: jones argues the design decisions behind both epochs could have been made as late as the shipwreck.For: The scheme uses a 205 BC epoch but the object was made later, in the second or first century BC, up to the…
  7. Asked on this site
Add evidence
1What it bears on2What you found3Where it comes from
Which answer?
Does it count for or against it?
In a sentence, what did you find?
What you found optional
Where it comes from optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.
Propose an answer
Your answer, in a sentence
What would rule it out? optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.
Ask a sub-question
Your question
Why it would help optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.
Add a source
The source
What it shows about this question optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.

Discussion 0

Add to the discussion