(link to book on Amazon) #5 CG on Science: On Seismology Now available as a Free PDF download For nearly a century (since 1936), research by Inge Lehmann has been used to establish the interior of the Earth has a mantle, a liquid outer core, and a solid inner core. CG on Science challenges those claims. Inge Lehmann's presentation of how P-waves are believed to travel through the Interior of the Earth can't possibly be valid. The interior of the Earth may very well have a mantle, a liquid outer core, and a solid inner core. The evidence used to establish the nature of the interior of the Earth is invalid. The data is fine. Our interpretation (application) of that data is invalid.