Human-powered cranes and lifting devices (2010) | Hacker News Reader

Human-powered cranes and lifting devices (2010)

lowtechmagazine.com

108 pointscodezero25 comments

Charles Singer's A History of Technology is an interesting read for similar concepts. Published 1954-58.

https://en.m.wikipedia.org/wiki/Charles_Singer

https://www.worldcat.org/title/history-of-technology/oclc/22...

For a shorter read I recommend The Medieval Machine by Jean Gimpel. It's a bit old now but tells an interesting story, turns out there was a lot more industrial machinery in the 13th century than we tend to think.

Definitely not the shortest read, my suggestion. Though it turns up on LibGen.

James Burke's Connections traces much of this historry, as does Vaclav Smil's Energy and Civilization.

The Singer ref should reward multiple interests, and can be dipped into at leisure.

The picture shown is of the moving of the Vatican obelisk from one side of St. Peters to the other. Took 5 months and far too large a crew for the job. The Romans had previously moved that obelisk from Egypt to Rome.

> The Romans had previously moved that obelisk from Egypt to Rome.

I wonder how many people died during this job. I mean: stuff is easier to do when you have a ton of expendable slaves no one cares about when they die or get injured.

I read somewhere that slaves were expensive and a valuable item. As well, every accident has an inherent risk of damaging either the item or equipment used for transportation which certainly were valuable.

The same logic applies to the pyramids of Egypt in antiquity, and tragically, much of the UAE today.

Maybe less than you think (deaths & slaves).

https://www.theguardian.com/world/2010/jan/11/great-pyramid-...

https://en.wikipedia.org/wiki/Egyptian_pyramid_construction_...

I'm surprised there doesn't seem to be a mention of the ingenious Chinese windlass. This was the best article I could find on it:

https://makezine.com/projects/make-25/the-chinese-windlass/

They aren't as great as often claimed. Since they rely upon potentially slight differences in diameter, any layering of cable on either side radically alters things. You have to be religious about policing the rope as it rolls onto the cylinder. This also limits the amount of cable that can be used to whatever can wind on without layering. So ya, it can raise an extremely heavy bit of bridge a few feet, but it isn't suitable for anything resembling a crane or hoist. It is great for lifting an engine block off its mounts, but not for lifting lumber up the side of a building.

Unusually well reseached and written. I'm sure pedants might find a few issues, but I feel like I learned something new, and significant from this.

Well written _as usual_ for lowtechmagazine! I suggest you dig through their website. Great stuff all around.

Exactly! One of my favorite sites. There's also "No Tech Magazine" with a bit different scope (and, sadly, less consisent quality) – http://www.notechmagazine.com/

Solid recommendation! There goes my weekend

I was under the vague, easily mind-changeable impression that we as modern humans would not be able to build the largest pyramids* in any reasonable amount of time (or even at all) using modern technology. This article makes it sound like cake. Just take a few guys with a big crane and in a couple years bam there you go.

Can anyone explain the dissonance?

*or maybe it was some other monolithic stone structure.

EDIT: Found some legitimate-sounding estimates here (first answer): https://answers.yahoo.com/question/index?qid=1006042514514

They probably weren't built in a reasonable amount of time. St Paul's cathedral took 35 years and "was the first English cathedral to be completed within its architect's lifetime." [1]

[1] http://www.engineering-timelines.com/scripts/engineeringItem...

I try to remember these things when I look at the modern cathedrals, in Germany's case the new Berlin Airport, the new Stuttgart railway station, and, recently completed, the Hamburg philharmonia building - also called the German Bermuda triangle for its ever increasing costs and time-frame.

In the long term, this was the normal way to build large structures, and hopefully future generations will look at them and still be able to enjoy, even if we have to pay more and more and keep waiting.

The Hoover Dam is a similar amount of material to the Great Pyramid. Took 5 years to build.

Three Gorges Dam is about 10 times the material.

Then there was the London to Birmingham railway line, built largely by hand, which was supposed to be more work by less people in less time.

"Peter Lecount, an assistant engineer of the London Birmingham railway, produced a number of - possibly hyperbolic - comparisons in an effort to demonstrate that the London and Birmingham Railway was "the greatest public work ever executed either in ancient or modern times".[4] In particular, he suggested that the effort to build the Great Pyramid of Giza amounted to the lifting of 15,733,000,000 cubic feet of stone by 1 foot (say, 450,000,000 m3 by 0.3 m).

The railway, excluding a long string of tasks – drainage, ballasting, and so on – involved the lifting of 25,000,000,000 cubic feet (say, 700,000,000 m3) of material reduced to the weight of stone used in the pyramid. The pyramid involved, he says, the effort of 300,000 men (according to Diodorus Siculus) or 100,000 (according to Herodotus) for twenty years. The railway involved 20,000 men for five years. In passing, he also noted that the cost of the railway in penny pieces, was enough to more than form a belt of pennies around the equator; and the amount of material moved would be enough to build a wall 1 foot (305 mm) high by one foot wide, more than three times around the equator."

https://en.wikipedia.org/wiki/London_and_Birmingham_Railway#...

The Hoover Dam also finished under-budget and ahead of schedule.

Building pyramids out of single stones is still very labor intensive. So modern technology might save a lot of workers in transporting the stone, but they still have to be placed individually. To see what modern technology can achieve, look at modern construction sites, like skyscrapers or especially the work done at the spillway of the Oroville dam after it broke. Large parts of the spillway had to be replaced in a couple of months, laying enough concrete to build a pyramid - I have to look up the exact numbers to see how large exactly. Additionally a huge amound of debris was removed from the waterway. All this by a few hundred workers working in 3 shifts. Check out the construction videos here: https://www.youtube.com/user/calwater/videos

For one thing, we don't operate at similar scales of human engineering. The Romans, for example, had huge armies. But the entire army was also experienced at engineering and building, to the point where whenever they weren't fighting, they were building fortifications and bridges, which gave them terrifying speed and technological superiority.

Build an army of construction workers, engineers and craftsmen today and you can build some pyramids. Hell, skyscrapers go up in China in like a month now.

This is a very interesting article, but many of the numbers are off.

The three foundation stones at Baalbek are estimated at 800 to 1100 tons each. The Romans never managed to move anything much over 300 tons -- one of the Egyptian obelisks had to be broken up so they could bring the top part to Rome.

Nobody knows who moved the stones at Baalbek, but they are much more deeply weathered than the Roman temples built on top. It is considered important that they did not need to be lifted, as they were quarried from higher than their final resting place.

> to lift weights that would be impossible to handle by most power cranes in operation today.

TlDr;

Modern construction techniques do not require lifting heavy blocks of stone, so no-one makes a machine to do it.

video of one in use

https://www.youtube.com/watch?v=GuJTm9aKuvs

youtube also has a segment saying they were used in modern prisons as "torture"

I feel it's coming back to slow climate change

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