Contents 1
Crossing the Sea 1
Movements of the Earth’s Water 3
Helicopters 6
The Ecosystem Concept 10
Atomic Smashers-50 Years 14
A Pollution Sensor 19
Antarctica 21
Unique Aircraft 25
Future City in the Sea 28
Zhan Tien-you—A Great Patriotic Engineer 32
Three UFOs—How Real Were They？ 38