As the book's cover states, the author explores the brilliant and prescient mind of one of the twentieth century's greatest scientists and inventors. Called madman by some, genius by others and an enigma by nearly everyone else, Nikola Tesla was without a doubt an amazing inventor. Tesla not only discovered the rotating magnetic field but introduced us to the fundamentals of robotics, computers, missile science, radio, concept of electromagnetic energy being transmitted "through the Earth", ball lightning, radar and many others.
This book gives a glimpse of a brilliant mind and at the same time a very lonely man (nothing negative here as Tesla was simply a loner, working apart, not entering into corporate associations and not mixing with friends). It covers his whole life, starting at his birth in Croatia in 1856 and his childhood. While in school he excelled in English, French, German, Italian, Slavic dialects and of course math at which he starred. At one point his math's teachers suspected him of cheating, but soon it was realized that this was just another aspect of his abnormal ability to visualize and retain images (his mind pretty much stored entire logarithmic tables to be called on as needed (p35)). According to him, he was also displaying another phenomenon that is familiar to many creative people: there always came a moment, when he was not concentrating, but when he knew he had the answer (even though it had not yet materialized). Practical results confirmed this intuition (it is a fact, that in later life the machines that he built nearly always worked).
In later parts of the book, we have a detailed description of his life in US, working with Edison, his famous Colorado Springs experiments and association with Colonel Astor, George Westinghouse or J.Pierpont Morgan. At that time the made almost correct prediction that Earth itself resonates at 6, 18 and 30 Hz - he was almost close to the mark as Earth resonates at 8, 4 and 20 Hz (since his wireless power-transmission concept involved Earth resonance, the closer he could bring his operational frequency to that of the Earth the better it would be for producing very large movements of power in his system (p178)).
The book is also very good at describing his later days, the fascination with pigeons that started with a "little sick bird" in his room, which he had picked up two days before in front of the library (this whole situation worried him much more than all his technical, wireless problems put together). That fascination with pigeons (saving them and feeding them), lasted pretty much until his death in 1943, at the age of 86 (Tesla died in his sleep). Some people could find this strange, but it simply was something that he "picked up" in his childhood: "I liked to feed our pigeons, chickens, and other fowl, take one or the other under my arm and hug and pet it" (p280).
In my opinion this is a captivating story of almost forgotten, fascinating man, a great mind, and some of the most amazing discoveries at the beginning of XX century. It is worth notice, that the US federal government had a great interest in Tesla's papers (probably because Tesla often talked about developing weapons with beams that would melt aircraft, telegeodynamics and other advanced concepts -> chapter 29 and partly 30 - will give you more information about that). The book also has a few pages of photos that are a nice addition to a whole story.
If you are interested in Nikola Tesla, you simply have to read this book. It will give you a small insight into one of the greatest minds of the XX century. You won't regret reading it (plus, each chapter has about 5 to 15 reference notes, and there is some additional information about Tesla's own writing and lectures in "Reference Notes" chapter (p357), so if you want to know more it is easy to find an additional material to read). A highly recommended read!