//detect browser:
browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);
if (browserName == "Netscape" && browserVer >= 3) browserVer = "1";
else if (browserName == "Microsoft Internet Explorer" && browserVer == 4) browserVer = "1";
else browserVer = "2";

//preload images:
if (browserVer == 1) {
a1 = new Image(72,29);
a1.src = "images/contact_us.jpg";
a2 = new Image(72,29);
a2.src = "images/contact_us_on.jpg";
}
if (browserVer == 1) {
b1 = new Image(50,29);
b1.src = "images/history.jpg";
b2 = new Image(50,29);
b2.src = "images/history_on.jpg";
}
if (browserVer == 1) {
c1 = new Image(82,29);
c1.src = "images/terminology.jpg";
c2 = new Image(82,29);
c2.src = "images/terminology_on.jpg";
}
if (browserVer == 1) {
d1 = new Image(72,29);
d1.src = "images/links.jpg";
d2 = new Image(72,29);
d2.src = "images/links_on.jpg";
}
if (browserVer == 1) {
e1 = new Image(72,29);
e1.src = "images/emergency_contacts.jpg";
e2 = new Image(72,29);
e2.src = "images/emergency_contacts_on.jpg";
}

//image swapping function:
function hiLite(imgDocID, imgObjName, comment) {
if (browserVer == 1) {
document.images[imgDocID].src = eval(imgObjName + ".src");
window.status = comment; return true;
}}