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profloater
2017-Jun-15, 07:51 PM
You know those jigsaw stones found in ancient Olmec, Aztec, Egyptian sites, ? Later ones were "modern" bricks or blocks with plane faces. Making plane faces is easy to understand. But how did those ancients make the curves and lumpy stones that fit together so well you cannot get a sharp edge in between them?
For me it's the biggest puzzle presented by the remains. I don't worry about why they did it or who they were, but how? Some stones are many tons, the quarries are found, but no sign of how they got those perfect fits, some or many without tool marks. It's like they were cast. Any ideas?

grant hutchison
2017-Jun-15, 08:15 PM
Scribing, graded hammerstones and repeated trial fittings. See Inca Quarrying and Stonecutting, Protzen 1985 (http://www.michaelsheiser.com/PaleoBabble/Inca%20Quarrying%20and%20Stonecutting.pdf) (6MB pdf).

Experiments show that with this process stones can be mined, cut, dressed, and fit with little effort and in a short time.

Grant Hutchison

WaxRubiks
2017-Jun-15, 09:53 PM
maybe you could do something like dentists do with a sort of carbon paper, and make one stone very black, eg with charcoal; put the stones together, and then you could see where they touch.

PetersCreek
2017-Jun-15, 09:58 PM
maybe you could do something like dentists do with a sort of carbon paper, and make one stone very black, eg with charcoal; put the stones together, and then you could see where they touch.

I watched a documentary some years ago in which they demonstrated that kind of technique. They placed one stone atop another, identified the high spots on the lower stone, and began chipping away at it with a tool stone. After a they made some progress, they left the chips/powder in place, and test fitted the upper stone. The impression left (or not) indicated where more tooling was needed.

profloater
2017-Jun-15, 11:17 PM
I like the hammer stones idea, the blocks are limestone, so you could work them, but being large, the effort to do trial fits seems enormous compared with aiming for flat surfaces. If they wanted interlocking, flats can be pegged. However I will look out for those demonstrations. Thanks for the feedback.

01101001
2017-Jun-16, 12:15 AM
I like the hammer stones idea, the blocks are limestone, so you could work them, but being large, the effort to do trial fits seems enormous compared with aiming for flat surfaces.

It's amazing what a person can accomplish if they don't use Facebook.

danscope
2017-Jun-16, 12:32 AM
Yes, but........ try fitting and re-fitting andesite ( a very hard granite ) weighing in at 50 to 100 tons , with a lot of peculiar angles,
notched into adjacent rocks of similar size and weight ? Now make a lot of it like the walls at Sacsayhuaman .
This is a mystery which has astonished me for 50 years. Just moving these monsters is quite a feat, and these things were moved over
many miles without roads and over mountains etc. Look some of this up on Youtube sometime. Pretty well filmed.

Reality Check
2017-Jun-16, 03:34 AM
I do not know how they did it but I would do the fitting & refitting with all the rocks horizontal on flat ground and then build the walls. The Saksaywaman (https://en.wikipedia.org/wiki/Saksaywaman#Theories_about_construction_of_walls) Wikipedia article has "rough-cut to the approximate shape in the quarries" so that would minimize any refitting at the site. Another possibility in the article is "templating" as suggested on A THEORY ON INCAS' STONE FITTING TECHNIQUES (http://www.davideandrea.com/personal/ideas/inca_stones/index.html) (create a stick & clay template of the gap to be filled and shape the rock to the template). The "scribing" method has only a broken link but may be a way of tracing the gap to be filled on the rock.

publiusr
2017-Jun-16, 08:14 PM
It's amazing what a person can accomplish if they don't use Facebook.

No mystery--no UFOs/laser.

It's called elbow grease--and want-to.

profloater
2017-Jun-16, 10:27 PM
I am guessing that the jigsaw stones are much better in an earthquake. Otherwise it still seems a plane interface would save so much time. Maybe that had experience of stones sliding and falling in tremors.

billslugg
2017-Jun-17, 06:42 PM
Yes, they were interlocked in order to allow them to settle back into place after an earthquake. The random sizes is due primarily to the fact that they used naturally fallen blocks as their raw material. Not dealt with in the article was how they moved the stones. Not mentioned was the fact that they used wooden forms, replicating the desired shape, to measure their progress. When the blocks went together, less rework was needed.

Reality Check
2017-Jun-18, 10:50 PM
Not dealt with in the article was how they moved the stones.
The Saksaywaman (https://en.wikipedia.org/wiki/Saksaywaman#Theories_about_construction_of_walls) Wikipedia article is quite clear on how the stones were moved.

They were dragged by rope to the construction site, a feat that at times required hundreds of men.[20] The ropes were so impressive that they warranted mention by Diego de Trujillo (1948:63 [1571]) as he inspected a room filled with building materials.
Inca Quarrying and Stonecutting, Protzen 1985 (http://www.michaelsheiser.com/PaleoBabble/Inca%20Quarrying%20and%20Stonecutting.pdf) (6MB pdf) excluded transportation.

The technological issue is, of course, the question of how the Incas managed to build such masonry. This problem may be formulated more succinctly with questions about the following operations: a) The quarrying. What kind of stone did the Incas select? How, and with what tools, did they extract it and break it up? b) The cutting and dressing. How, and with what tools, were these operations performed and where? c) The fitting and laying. With what technique and what devices did the Incas achieve the proverbial fit between stones? d) The handling and transportation. How, and with what devices, did the Incas transport and lift the building stones? On the basis of my research in the Cuzco area in I982 and 1983, I can provide answers to the questions about the first three operations.
I suspect that neither article states that wooden forms were definitely used because no wooden forms have been found. So the Wikipedia articles suggests a couple of methods and the older article is the author trying out his method.

profloater
2017-Jun-18, 11:53 PM
if they had hundreds of workers and impressive ropes, could they have arranged to slide the stones sideways with abrasives in between? Some degree of preshaping would be done, I guess, but the final fit could be by wearing the stones down in that way with gangs of pullers. That would mean only lifting the stones once. If that was done with earth/wooden ramps, the only method I can think of at the moment, you would not want to do it often. It makes the ropes with loads of pullers a prime mover to be used in various ways. Even with that, a crane system seems unlikely, some stones are many tons. However my idea puts a rope in the way of the final fit. It would imply smaller infill stones which could be man handled into the gaps.

grant hutchison
2017-Jun-19, 12:27 AM
If that was done with earth/wooden ramps, the only method I can think of at the moment, you would not want to do it often.I think "you would not want to do it often" isn't an exclusion criterion for many activities in societies different from our own. The people who did this stuff probably didn't want to do it often, but they had no choice.
A bit like my painting my mother's railing fence today (and tomorrow, and the next day, and the day after that).

Grant Hutchison