function calc_nav_height()
{
  var browser = '';
  
  browser = navigator.appName;
  // test line 
  //alert ("before if stmt - browser: " + browser);
  
  if(browser == "Microsoft Internet Explorer")
  {
    var pageHeight = document.body.scrollHeight;
	//alert ("in IE - boo: "+ browser);
  }else if(browser == "Netscape")
  {
    var pageHeight = document.body.offsetHeight;
	//alert ("in Netscape - boo: "+ browser);
  }
  
  var headerHeight = document.getElementById("headerTable").offsetHeight;
  var navHeight = document.getElementById("TDnav").offsetHeight;
  //var addressHeight = document.getElementById("TDbottom").offsetHeight;
  //var finalHeight = (pageHeight - headerHeight - navHeight - addressHeight);
  var finalHeight = (pageHeight - headerHeight - navHeight); 
  var tdbelowNav = document.getElementById("TDbelowNav");
  tdbelowNav.style.height = finalHeight+"px";
  
  // This section grows table in Dept.asp, Product & search.asp 
  //under the artculture & shop image
  
  // 1st check if on td we need to grow on page 
  // by using eval() method to see if it that ID exists
  var exists = eval(document.getElementById("TDbelowImage"));
  if (exists) {   
  	
	  //get full height of left nav pulled by ID= "navTable"
	  // set on outer table in deptlinks.asp  (in the 'above links' field)
	  var fullHeight = document.getElementById("navTable").offsetHeight;  
	  //height of image artculture & shop - jmuseum_rt_col.jpg
	  var rightCol = 504; 
	  
	  //create var from td we want to grow (td under image)
	  var tdGrow = document.getElementById("TDbelowImage");
	
	  //height of left nav -(minus) height of image = amt needed to grow
	  // the td under image so it meets footer
	  var amtGrow = fullHeight - rightCol;
	  
	  // only set height or grow if positive number
	  if (amtGrow > 0 ){
	  	tdGrow.style.height = amtGrow+"px";
	  } // end if amt greater than zero
	  
	  /**test lines alert ("full: " +fullHeight); 
	  * alert ("rightCol: " +rightCol); 
	  * alert ("growth: " + amtGrow); **/
  } // end if right column td exists
  
} // end function