function loadOne() {
changeImages('x','img/nav/con_1.jpg'); 
setTimeout("loadTwo()",500);
}
function loadTwo() {
changeImages('x','img/nav/con_2.jpg'); 
setTimeout("loadOne()",500);
}
setTimeout("loadOne()",500);
function newImage(arg) {
if (document.images) {
rslt = new Image();
rslt.src = arg;
return rslt;
}
}
function changeImages() {
if (document.images && (preloadFlag == true)) {
for (var i=0; i<changeImages.arguments.length; i+=2) {
document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
}
}
}
var preloadFlag = false;
function preloadImages() {
if (document.images) {
con_1 = newImage("img/nav/con_1.jpg");
con_2 = newImage("img/nav/con_2.jpg");
preloadFlag = true;
}
}