// Keep track of what "page" of the contents that we're currently on
  var curPage = 1;
  
  // Make sure that we don't load a page twice, at the same time
  var loading = false;
  
  // We're going to see if we should load some more content based upon where
  // the user is currently located on the page
  window.onscroll = function(){
      // We need to verify a couple things before we try and load some more contents
      // 1) We need to make sure that we're not at the last page of contents.
      // 2) We need to make sure that we're not already loading some new posts.
      // 3) We're only going to load new posts if we're scrolled near the bottom of the page
      if ( curPage >= 1 && !loading && pageHeight() - scrollY() - windowHeight() < windowHeight() ) {
  
          // Remember that we've started to load the new posts.
          loading = true;
  
          // Load the posts using our handy ajax() function
          ajax({
  
              // We're just requesting a simple web page, so just use GET
              type: "GET",
  
              // We're expecting an RSS feed, which is just an XML file
              data: "xml",
  
              // Get the RSS feed of the Nth page. When we first load this page
              // we're on page '1', so we start at 2 and work our way back in time
              url: "./?feed=rss&paged=" + ( ++curPage ),
  
              // Watch for when the RSS feed has been successfully retrieved
              onSuccess: function( rss ){
  
                  // We're loading the new posts into the <div> that has an ID of "content"
                  var content = document.getElementById("content");
  
                  // We're going to iterate through each of the posts in the RSS feed
                  var items = rss.getElementsByTagName("item");
                  for ( var i = 0; i < items.length; i++ ) {
  
                      // Place the new entry into the document
                      content.appendChild( makePost( items[i] ) );
  
                  }
  
                  // If there are no items to retrieve from the XML document,
                  // we must be back as far as we can go
                  if ( items.length == 0 ) {
                      curPage = 0;
                  }
              },
  
              // Whenever the request has completed, we can try to load new items again
              onComplete: function(){
                  loading = false;
              }
          });
      }
  };
  
  // A function for creating the complex DOM structure of a single post
  function makePost( elem ) {
      // Lets extract the Link, Title, and Description data from each feed post
      var data = getData( elem );
  
      // Creating a new wrapper <div> to hold the post
      var div = document.createElement("div");
      div.className = "post";
  
      // Create the post header
      var h2 = document.createElement("h2");
  
      // This holds the title of the feed and has a link that points back to the post.
      h2.innerHTML = "<a href='" + data.link + "'>" + data.title + "</a>";
  
      // Add it in to the post wrapper <div>
      div.appendChild( h2 );
  
      // Now lets create a <div> to hold the long post contents
      var entry = document.createElement("div");
      entry.className = "entry";
  
      // Add the contents to the inside of the <div>
      entry.innerHTML = data.desc;
      div.appendChild( entry );
  
      // Finally, lets add a footer that links back
      var meta = document.createElement("p");
      meta.className = "postmetadata";
      meta.innerHTML = "<a href='" + data.link + "#comments'>Comment</a>";
      div.appendChild( meta );
  
      return div;
  }
  
  // A simple function for extracting data from a DOM element
  function getData( elem ) {
      // We're going to return the data as a nicely formatted object
      return {
          // Extract the title, description, and link from the rss feed <item> element
          title: elem.getElementsByTagName("title")[0].firstChild.nodeValue,
          desc: elem.getElementsByTagName("description")[0].firstChild.nodeValue,
          link: elem.getElementsByTagName("link")[0].firstChild.nodeValue
      };
  }