    sentence t since few giimina ‘arid, cosmig"iayé can pass  through our atmosphere, Gin wa iintage Eaith with:-thom  {and ubing theit penetration mage its substirfacd?    Santenes 2:Since: some. gamma, and ‘cosmic rays.pass  through our atrriosphere ‘could We také advantage of their  periétration power and, get an irnage: of the subsurface  with them?