Dear Thea,

The King's Chamber is 5x10 times the volume of the coffer. 5 cubic pyramid inches of earth of average density has the same mass as 1/(50x50) of the coffer's volume of water at a temperature that is 1/5th the difference between freezing and boiling. The coffer's interior volume is 50*50*50 cubic pyramid inches times 5.7, divided by 10. ................
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