var image = new Array();
image[0] = 'resources/header01.gif';
image[1] = 'resources/header02.gif';
image[2] = 'resources/header03.gif';
image[3] = 'resources/header04.gif';
image[4] = 'resources/header05.gif';
image[5] = 'resources/header06.gif';
image[6] = 'resources/header07.gif';
image[7] = 'resources/header08.gif';

var j = 0
var p = image.length;
var preBuffer = new Array()
for (i = 0; i < p; i++){
   preBuffer[i] = new Image()
   preBuffer[i].src = image[i]
}
var whichImage = Math.round(Math.random()*(p-1));
function showImage(){
document.write('<img src="'+image[whichImage]+'"ALT="ICES Header">');
}