- When visiting Bath[1] in UK (mentioned in the article), I learned the Romans used a clever contraption, the "three legged lewis", to lift heavy stones[2].
Referring to the diagram[3] on Wikipedia, a concave hole is first cut into the stone. Parts 1 and 2 of the lewis are inserted, one at a time. Inserting part 3 between 1 and 2 results in all three locking into place. A pin and ring at the top keeps the 3 parts from separating.
[1] https://www.romanbaths.co.uk
[2] https://bathgeolsoc.org.uk/journal/articles/2021/2021_Moving...
[3] https://en.wikipedia.org/wiki/Lewis_(lifting_appliance)#/med...
by pugworthy
2 subcomments
- Though really amazing engineering, I'd say not all of them show "how they pulled it off". I'd like to know how the Byzantine geared mechanical calendar was "pulled off", especially those gears.
by dtgriscom
1 subcomments
- The article lists a "Snake Bridge on the Macclesfield Canal". Here's a spiral bridge on that canal, but not the same one:
https://www.google.com/maps/place/Spiral+Bridge/@53.2849203,...
https://www.google.com/maps/place/Spiral+Bridge/@53.2850202,...
by ProllyInfamous
0 subcomment
- If you liked the Snake Bridge, check out US 441 as it passes (around itself) through Great Smokey National Park (Newfound Gap). The road literally underpasses itself in a very tight loop.
[•] https://www.loc.gov/pictures/resource/hhh.tn0278.photos.3658...
by NathanielBaking
0 subcomment
- Fascinating! I would buy this in a "coffee table" style book.
by Barathkanna
2 subcomments
- Cool to see how much engineering relied on intuition and improvisation before modern tools existed. These methods look primitive now, but they worked because people understood materials so well. Makes me wonder how much of that hands-on knowledge we’re losing today.
- Quibble: I hate, despise, loathe the dilution of the word "rare" to mean, well, in this case "somewhat interesting and not commonly known".
Photos cannot be rare. Physical copies of a photograph might be. Photos are by their nature singular instances of artistic or technical action, so all of them are equally rare.
- the iranian windmills were not expected, neither the absorbing layers of south american cultures brilliant
by unsignedchar
0 subcomment
- Interesting collection but mostly focused on western world and mixing different eras so feels incoherent, like a low-effort ‘content creation’
- [dead]
- This article seems to focus mainly on Western civilization. Not saying they aren't wonders. There were many engineering feats in the South/East Asian subcontinents that are not covered.
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