Direct-authored thread on the Giant's Causeway's basalt columns and their parallels at Fingal's Cave, South America, and India.

Giant's Causeway: Nature's Masonry

The Giant's Causeway: thousands of basalt columns, mostly five-sided, fitting together so closely the book compares them to vertebrae.

Giant's Causeway: Nature's Masonry

The same basalt-column formation appears at Fingal's Cave on Staffa — different island, identical natural process.

Giant's Causeway: Nature's Masonry

The book notes similar columns turning up in South America and India.

No mason traveled between any of them.

Giant's Causeway: Nature's Masonry

Cooling basalt cracks into these shapes wherever the conditions are right.

‘Masonry’ here has no mason at all.

Giant's Causeway: Nature's Masonry