codes we have in the exhibit, in this case is calvin titus. titus won a medal of honor for daring and galant conduct, he was one of the first soldiers to scale the walls of peking during the boxer rebellion. this q.r. code will take your cell phone to a recording of his actual oral history. >> this is something that took place a long time ago and it's followed me. i can't get away from it. >> but the wall looks like the one you scaled? >> yes, that's a very good representation of it. of course, as you see that fellow standing on top there now, that would have been impossible. that thing those stones are round up on top and narrow and nobody could stand up there unless he was an acrobat. >> what did you think at the time you were scaling it, were you sure you would make it or did you have doubts about it? >> well, i thought i'd make it all right. i wasn't very much afraid of that because i was a fairly good climber. but of course i never thought about what i was getting into. ( laughter ) >> i understand that when president the door roosevelt p