Countless brick-typed stones are used in Great Zimbabwe ruins in Africa.
Where did those stones come from?
The high towers were made by piling up the brick-typed stones.
What are the glue of these stones?
How were the natural stones and these brick-typed stones glued ?
https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQkDbsQDNbpc_0G4P1Mnue9iUuygNhyBWsh-4nxDlycCEoY1XC82Q
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https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcTGElaLDqbApNyWBtB94u8BlNHMfjd5w0TdQQHHpfaUr2Kyl-en
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https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcSOoE9OeeKkh9mGtYFHgfq_EjNbETetcra-wyLNouiHRUB-HK5L
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https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcRigx6NxXVCKuja6mmFCHGtWnJmadszKmAVudrTi_WjJLrBof44
https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcRvMpo49VPmGXO8BbvQGxHs_2RtYWjGGH09-d6amCeBsuOTzHNQ1A
http://bushsafari.files.wordpress.com/2011/02/great-zim-2.jpg
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https://monomutapaland.files.wordpress.com/2009/08/gzentrance.jpg
As the ceiling of this gate is not the arch, I wonder why it didn't fall down.
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http://www.sekai-isshu.com/photo/africa/zimbabwe/2_01.jpg
As the ceiling of this gate is not the arch, I wonder why it didn't fall down.
https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcR5dXbd4E2UvNHJ_sWHBkpaIT2k0i5suJS-QS7_KOogOxe92omD
https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcSXz4xqEl4hQOqXg-aiUwyjpsVSEpXZ2uf0KHvR7FhK_Y5CXKmw
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https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcRIoQj0nOl9XhQ5U4x1dSPKOxGvtF-AFtzD1CCVWpQCR4DyVqeYag
https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcTp2hhSkzHndvEmuYz1w7aYEWoKRAsBUxDqTznkzR_1whwy5qUl
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https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcSdGr0U8RiBaPL0LUeWF8NPynQpRWpmOe24jdR8SbYIabRNuvpznw
As the ceiling of this gate is not the arch, I wonder why it didn't fall down.
https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTnpFODqSp82l3JNPrAHFUWfPSrJXQg7IyEPxkOT6Q-GACrbRJ3
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