The following code shows how to create alert message block with arrow down icon.
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css"
href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.0/css/bootstrap-combined.min.css">
<script type='text/javascript'
src="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.0/js/bootstrap.min.js"></script>
<link rel="stylesheet" type="text/css"
href="http://netdna.bootstrapcdn.com/font-awesome/3.0.2/css/font-awesome.css">
</head><!--from w w w . j a va 2 s. co m-->
<body>
<p class="alert alert-info">
Example of Navbar with icons <i class="icon-arrow-down"></i>
</p>
</body>
</html>