Pioneers may achieve a lot, they are often not the most relaxed people to deal with. So it is not really a surprise to read that Thomas Edison was a rather nasty person, who would not hesitate to electrocute dogs (and in one case an elephant), just to show how dangerous ac current, as produced by his rival George Westinghouse, was.
Many of the stories Hal Hellman tells in this book have been related before. Still there are some lesser known gems, notably the life of Hyman Rickover, the man who had the first nuclear submarine built, and in the process fought almost everybody else in the American navy. As his biographer noted: "He believed the shortest distance between two points was a straight line - even if it bisected six admirals".
The Rickover chapter is the best, because it confines itself to its subject, the 'colourful' character, in stead of attempting to write the history of the whole surrounding field. Had mr. Hellman confined himself to this approach in the other chapters as well, his book would have been more balanced. Nonetheless, this is a perfectly enjoyable read.