Photo: Courtesy of the Tesla Memorial Society of New York
One of Tesla's closest friends was Mark Twain, seen here in Tesla's Fifth Avenue lab. Here, Tesla perfected his high-frequency coil (Photo 2), and transmitted long-distance radio signals up the Hudson River to West Point, N.Y. Tesla lost the lab in a fire, described by author Samantha Hunt. Despite this, Tesla was able to file for the first radio patent in the U.S., Patent No. 645,576.
