function createXmlHttpRequestObject() 
{
  // will store the reference to the XMLHttpRequest object
  var xmlHttp;
  // this should work for all browsers except IE6 and older
  try
  {
    // try to create XMLHttpRequest object
    xmlHttp = new XMLHttpRequest();
  }
  catch(e)
  {
    // assume IE6 or older
    var XmlHttpVersions = new Array("MSXML2.XMLHTTP.6.0",
                                    "MSXML2.XMLHTTP.5.0",
                                    "MSXML2.XMLHTTP.4.0",
                                    "MSXML2.XMLHTTP.3.0",
                                    "MSXML2.XMLHTTP",
                                    "Microsoft.XMLHTTP");
    // try every prog id until one works
    for (var i=0; i<XmlHttpVersions.length && !xmlHttp; i++) 
    {
      try 
      { 
        // try to create XMLHttpRequest object
        xmlHttp = new ActiveXObject(XmlHttpVersions[i]);
      } 
      catch (e) {}
    }
  }
  // return the created object or display an error message
  if (!xmlHttp)
    alert("Error creating the XMLHttpRequest object.");
  else 
    return xmlHttp;
}

function getEnlarged(image, divID, caption) {
	document.images[1].src=image;
	document.getElementById("caption").innerHTML = caption;
}

function getThumbs(dataSource, divID) {
	
	var xmlHttp = createXmlHttpRequestObject();
	
	if(xmlHttp)
	{
		var obj = document.getElementById(divID);
		xmlHttp.open("GET", dataSource);
		
		xmlHttp.onreadystatechange = function()
		{
			if(xmlHttp.readyState == 4 && xmlHttp.status == 200) 
			{
				obj.innerHTML = xmlHttp.responseText;
			}
		}
		xmlHttp.send(null);
	}
}

function swapImages() {
	temp = document.images[0].src;
	for (i=0;i<3;i++) {
		document.images[i].src=document.images[i+1].src;
	}
	document.images[3].src=temp;
}