function timeline() {
	var height = 410;
	var width = 720;
	features='toolbar=no,location=no,status=no,menubar=no,scrollbars=no,resizable=yes,width=' + width + ',height=' + height ;
	var result = window.open("documents/timeline.pdf", "window", features);
	}
	
function teachersguide() {
	var height = 410;
	var width = 720;
	features='toolbar=no,location=no,status=no,menubar=no,scrollbars=no,resizable=yes,width=' + width + ',height=' + height ;
	var result = window.open("documents/20040970_guide.pdf", "window", features);
	}
	
function smithsonian() {
	var height = 410;
	var width = 720;
	features='toolbar=no,location=no,status=no,menubar=no,scrollbars=no,resizable=yes,width=' + width + ',height=' + height ;
	var result = window.open("http://www.americanhistory.si.edu", "window", features);
	}