var theImages = new Array() // do not change this

theImages[0] = '/includes/banners/banner-index1.jpg'
theImages[1] = '/includes/banners/banner-index2.jpg'
theImages[2] = '/includes/banners/banner-index3.jpg'
theImages[3] = '/includes/banners/banner-index4.jpg'


var j = 0
var p = theImages.length;
var preBuffer = new Array()
for (i = 0; i < p; i++){
   preBuffer[i] = new Image()
   preBuffer[i].src = theImages[i]
}
var whichImage = Math.round(Math.random()*(p-1));
function showImage(){
document.write('<img src="'+theImages[whichImage]+'" border=0 alt="A Whole World of Microscopy Knowledge">');
}