I'm doing a report this Friday on Edison, Westinghouse and Tesla. I've seen photos of Mark Twain in Tesla's laboratory and know they were friends. But tonight I've heard more and wonder what the truth of it is. Here is a link I stumbled upon where a man reports that Twain and Tesla used to aim X-ray "guns" at each other. (Lasts less than 3 minutes) http://huffduffer.com/gentusmaximus/24278 Subsequently I've learned that indeed Tesla DID produce on of the first xray pictures, which he called "shadowgraphs" in the US and was complimented by Roetingen for his xray pictures. (One radiologist remarked that if Tesla's laboratory hadn't burned down, he may have gotten a Nobel Prize for some of his work.) Anyway, it was said by guy in this link that many of those Twain xrays exist. Do they? Does anybody know? Just curious. Arianne Laidlaw