THE FIRST SU C H A TT E M PT THE AMBITIOUS...

819. The first su c h a tt e m pt the ambitious Project Mohole, got under way during the 1960's and proved theAvalue of deep-sea drilling by making several t e st ho l e s in the mantle beneath the crust beforeBsp i ra l c os t s led to it s ca n c e ll a ti on .C D