function newImage(arg) {
    rslt = new Image();
    rslt.src = arg;
    return rslt;
}

function bOver(image) {
    document.getElementById(image).src = eval(image +"_on.src");
}

function bOut(image) {
    document.getElementById(image).src = eval(image +"_off.src");
}

about_dart_off = newImage('images/menus/learn/about_dart.gif');
about_dart_on = newImage('images/menus/learn/about_dart_on.gif');

mission_off = newImage('images/menus/learn/mission.gif');
mission_on = newImage('images/menus/learn/mission_on.gif');

dart_facts_off = newImage('images/menus/learn/dart_facts.gif');
dart_facts_on = newImage('images/menus/learn/dart_facts_on.gif');

history_off = newImage('images/menus/learn/history.gif');
history_on = newImage('images/menus/learn/history_on.gif');

staff_off = newImage('images/menus/learn/staff.gif');
staff_on = newImage('images/menus/learn/staff_on.gif');

affiliates_off = newImage('images/menus/learn/affiliates.gif');
affiliates_on = newImage('images/menus/learn/affiliates_on.gif');
tell_friend_off = newImage('images/tell_friend.gif');
tell_friend_on  = newImage('images/tell_friend_on.gif');