if (document.images) {

nav1_home_on = new Image();
nav1_home_on.src = "images/nav1_home_on.gif";
nav1_home_off = new Image();
nav1_home_off.src = "images/nav1_home_off.gif";

nav1_current_on = new Image();
nav1_current_on.src = "images/nav1_current_on.gif";
nav1_current_off = new Image();
nav1_current_off.src = "images/nav1_current_off.gif";

nav1_archive_on = new Image();
nav1_archive_on.src = "images/nav1_archive_on.gif";
nav1_archive_off = new Image();
nav1_archive_off.src = "images/nav1_archive_off.gif";

nav1_citing_on = new Image();
nav1_citing_on.src = "images/nav1_citing_on.gif";
nav1_citing_off = new Image();
nav1_citing_off.src = "images/nav1_citing_off.gif";

nav1_global_on = new Image();
nav1_global_on.src = "images/nav1_global_on.gif";
nav1_global_off = new Image();
nav1_global_off.src = "images/nav1_global_off.gif";

nav1_symposium_on = new Image();
nav1_symposium_on.src = "images/nav1_symposium_on.gif";
nav1_symposium_off = new Image();
nav1_symposium_off.src = "images/nav1_symposium_off.gif";

nav2_news_on = new Image();
nav2_news_on.src = "images/nav2_news_on.gif";
nav2_news_off = new Image();
nav2_news_off.src = "images/nav2_news_off.gif";

nav2_calendar_on = new Image();
nav2_calendar_on.src = "images/nav2_calendar_on.gif";
nav2_calendar_off = new Image();
nav2_calendar_off.src = "images/nav2_calendar_off.gif";

nav2_about_on = new Image();
nav2_about_on.src = "images/nav2_about_on.gif";
nav2_about_off = new Image();
nav2_about_off.src = "images/nav2_about_off.gif";

nav2_candidates_on = new Image();
nav2_candidates_on.src = "images/nav2_candidates_on.gif";
nav2_candidates_off = new Image();
nav2_candidates_off.src = "images/nav2_candidates_off.gif";

nav2_contact_on = new Image();
nav2_contact_on.src = "images/nav2_contact_on.gif";
nav2_contact_off = new Image();
nav2_contact_off.src = "images/nav2_contact_off.gif";


}
function turnOn(imgName) {
        if (document.images) {
        	document[imgName].src = eval(imgName + "_on.src");
        }
}
function turnOff(imgName) {
        if (document.images) {
        	document[imgName].src = eval(imgName + "_off.src");
        }
}