This goes in the header:

<style type="text/css">
/* image cacheing: 
Any images contained in this div will be loaded offscreen, and thus cached. */
@media projection, screen {
     div.imgCache { position: absolute; left: -8000px; top: -8000px; }
     div.imgCache img { display:block; }
}
@media print { div.imgCache { display: none; } }
</style>


****************************************************************


This div goes just inside the body:

<DIV class="imgCache">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
<img src="images/image.jpg">
</div>