Using jQuery to add HTML element doesn't work

Using jQuery to add HTML element doesn't work

Hello everyone: 

I am trying to add a paragraph by using jQuery, but the paragraph won't display in the browser. 
Please review my code and give me some feedback on why the paragraph didn't show. Thanks!

  2. <html>
  3.  
  4. <head>
  5.   <title>hello world</title>
  6.   <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
  7.  
  8.   
  9.   <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js" ></script>
  10.  <script language="JavaScript" type="text/javascript">
  11.   <!--
  12.   $(document).ready(function(){
  13.   if($('<p>this is a new paragraphy</p>').is(':visible'))
  14.   {
  15.     $('p').show();
  16.   }
  17.   });
  18.   //-->
  19.  </script>
  20. </head>

  22. <body>
  23.   
  24. </body>
  25. </html>