It's hard to believe, but the words “time” and “travel” were never really linked until H.G. Wells' 1895 novel,  “The Time Machine.” James Gleick, author of “Time Travel: A History”  discovered that everything from Mr. Peabody's Wayback Machine to Doc Brown's DeLorean can be traced back to Wells. “He wasn't trying to say anything about science,” Gleick says. “In order to tell his story, he invented this gimmick.” And “The Time Machine” explained this gimmick with another bit of sci-fi whimsy: that time is the fourth dimension of space. “That was ten years before Einstein's first publication of the special theory of relativity,” Gleick says. And once Einstein validated this view of space-time, it inspired countless stories about characters visiting the past and the future.