Anyone who denies that machining and moving of rock that we still cannot replicate happened in antiquity should read Chris Dunn’s books and watch this video featuring Russ Allen.
Russ Allen points out that many major constructions such as the Serapeum, Osireion, obelisk at Aswan, and large blocks at Baalbeck and the Yangshan Quarry in china are unfinished and that this displays the techniques being employed. Whatever civilisation did this they could remove granite as though it were butter. We are gaining hints as to how this might be possible through the work of Malcolm Bendall and Bob Greenyer – harnessing magnetic monopoles and ball lightning can disintegrate matter.
The marks left in the rock indicate the use of large, carefully controlled machines. These must have been made of metal. There is no other material that could produce the scoop marks under the unfinished obelisk. This begs the question of why there is no evidence left of them. Large amounts of iron would leave detectable iron oxide. Stainless steel would survive many thousands of years. The complete cessation of work on these constructions suggests a major sudden global disaster but the absence of evidence of the machines suggests organised withdrawal.
The younger dryas impact hypothesis can provide the disaster but where did the machines go?