Franklin Museum in Philly--back in the 70s (so it seems anyway) they had an enlarged walkthrough heart. You could enter it and follow the pathway that blood would follow to get oxygen. There was a (a la Dark Side of the Moon) heart beat piped in through out the experience--and it was very strange and neat to see the valves and heart muscles up close (not to mention, sad to say, some of the use and abuse left behind by visitors--graffitti messages or gum wads--left in little ventricles here and there). ========================================================= Important Subscriber Information: The Museum-L FAQ file is located at http://www.finalchapter.com/museum-l-faq/ . You may obtain detailed information about the listserv commands by sending a one line e-mail message to [log in to unmask] . The body of the message should read "help" (without the quotes). If you decide to leave Museum-L, please send a one line e-mail message to [log in to unmask] . The body of the message should read "Signoff Museum-L" (without the quotes).