Early hominids in east Africa fashion the earliest stone tools. The world gets its first glimpse of a functional internal combustion engine that uses coal gas as fuel. And the atomic era begins with a frightening flash, changing life as we know it forever. More than two million years of science and technology unfold, with all the milestone achievements in biology, chemistry, and physics placed in their broader social context and shown in plentiful images. The far-ranging feats include everything from the anonymous invention of the sewing needle to heart transplants.