function calc_nav_height()
{
  var browser = '';

  browser = navigator.appName;
  //alert ("before if stmt - browser: " + browser);
  //checks IF browser is IE
  if(browser == "Microsoft Internet Explorer")
  {
    //set page height into varible
    var pageHeight = document.body.scrollHeight;
	//test -alert ("in IE - boo: "+ browser);
    var browserDiff = 100 //350;

 //if not IE then "else if" browser Netscape/FF?  both will return Netscape
  }else if(browser == "Netscape")
  {
    //set page height
    var pageHeight = document.body.offsetHeight;
	//alert ("in Netscape - boo: "+ browser);
    var browserDiff = 100 //265;
  }
  //make sure the header table has the ID="headerTable"
  var headerHeight = document.getElementById("headerTable").offsetHeight;
  // the first TD  with any content should id="TDnav" often second table
  var navHeight = document.getElementById("TDnav").offsetHeight;

  //td after links with follow cart
   var cartHeight = document.getElementById("TDbelowNav").offsetHeight;

   //final height to grow TD is the full page height - all the others
   //browserDiff is subtracts different amounts due to browser (see above)
  var finalHeight = (pageHeight - (headerHeight + navHeight + cartHeight + browserDiff));
//alert(pageHeight - (headerHeight + navHeight + cartHeight + browserDiff));
 //this finds the TD you want to grow and puts it in a variable
  var tdgrow = document.getElementById("TDGrow");

  //this sets the height of the td that grows
  //check the source of the page and u should see style="height:NNpx;"
  if (finalHeight > 0){
  tdgrow.style.height = finalHeight+"px";
}

  /** lines to test how it works in each browser
  to see the numbers remove comments in front of each line BELOW **/
   //alert ("full height: " +pageHeight);
  //alert ("header height headerTable: " +headerHeight);
  //alert ("nav height TDnav: " + navHeight);
  //alert ("cart TDbottom: " + cartHeight);
  //alert ("amt it should grow: " + finalHeight);

  /** THEN
  1) either cut and past this code into bottom of the footer
  or include this file with the lines below
  <script src="assets/images/hickeystyle/includes/calc_nav_height_commented.js"></script>

   2) add this to the BODY tag in STYLES section of the manager
   onLoad="calc_nav_height();"   ex.<body onLoad="calc_nav_height();">  **/

} // end function	