"Ex-library with expected markings. Tight, bright, clean and square but has sticker remnants on lower part of spine and black marker line on bottom of text block and front endpapers. Early pictorial cover, no dust jacket. ""We live on the face of a planet that is almost a complete mystery...many mysteries remain unsolved...One of the greatest is - just what lies inside our planet? Exactly what makes up our world? "" 160 indexed pages including Bibliography and illustrated with black and white drawings. Large type face would seems to indicate it was intended or Middle School level. Content is appropriate up to adult. "