peopleon=new Image();
peopleon.src="people_on.gif";
facilitieson=new Image();
facilitieson.src="facilities_on.gif";
historyon=new Image();
historyon.src="history_on.gif";
homeon=new Image();
homeon.src="home_on.gif";
courseson=new Image();
courseson.src="courses_on.gif";
publicationson=new Image();
publicationson.src="publications_on.gif";
publicon=new Image();
publicon.src="public_on.gif";
gallerieson=new Image();
gallerieson.src="galleries_on.gif";

peopleoff=new Image();
peopleoff.src="people.gif";
facilitiesoff=new Image();
facilitiesoff.src="facilities.gif";
historyoff=new Image();
historyoff.src="history.gif";
homeoff=new Image();
homeoff.src="home.gif";
coursesoff=new Image();
coursesoff.src="courses.gif";
publicationsoff=new Image();
publicationsoff.src="publications.gif";
publicoff=new Image();
publicoff.src="public.gif";
galleriesoff=new Image();
galleriesoff.src="galleries.gif";

function imgOn(whichButton) {
  document.images[whichButton].src=eval(whichButton+"on.src");
  }
function imgOff(whichButton) {
  document.images[whichButton].src=eval(whichButton+"off.src");
  }