Summary: Bob Garfield and Mike Vuolo discuss the energetic history of the word sleep.<br><br>Lexicon Valley is brought to you by The Message, an original science fiction podcast from Panoply and GE Podcast Theater. All of Season 1 is available now, so listen and find out why a 70-year-old alien recording seems to be killing people. Search for The Message on iTunes.<br><br>Join<strong> Slate Plus</strong>! Members get bonus segments, exclusive member-only podcasts, and more. Sign up<br>for a free trial today at <a href="http://www.slate.com/podcastsplus">www.slate.com/podcastsplus</a>.<br><br>Twitter: @lexiconvalley<br>Facebook: facebook.com/LexiconValley<br>Email: <a href="mailto:lexiconvalley@slate.com">lexiconvalley@slate.com</a>
