// global variable for current sponsor - sets default/loading image
var sponsor = num;  // starting image (1,2...)
var maxsponsors = 7;  // max sponsors (1,2...)

// function to link to appropriate sponsor
function GoSponsor() {
	window.open ("http://www.americanherniasociety.org/alliances.cfm");
}

// function to rotate image (currently uses 2 images)
function rotate() {
   if (++sponsor > maxsponsors)  sponsor = 1;

   document.images["alliance"].src = "http://www.americanherniasociety.org/images/sponsor_" + sponsor + ".gif";

   window.setTimeout('rotate();',5000);
}