What was the name of the biographer who wrote 'Prodigal Genius: The Life of Nikola Tesla'?

John J. O'Neill wrote Prodigal Genius: The Life of Nikola Tesla. The biography was published in 1944 and became one of the best-known early book-length accounts of Tesla's life and work.

O'Neill was a science journalist associated with the New York Herald Tribune. His full name was John Joseph O'Neill, but the book and reference works commonly identify him as John J. O'Neill, making the stored answer the canonical quiz response. He was also a Pulitzer Prize-winning science reporter and had known Tesla personally.

Prodigal Genius covered Tesla's inventions, his rivalry with Thomas Edison, the War of the Currents, wireless technology, and his later years in New York. It also helped shape the popular image of Tesla as an eccentric, visionary inventor. Readers may confuse the author with George Westinghouse, Tesla's business partner in developing AC power, or with Edison, Tesla's former employer; neither wrote this biography.