var snippet = new Array();

//Add to the following section for additional random snippets.
snippet[0] = '<img src="http://library.cnu.edu/images/library1.jpg" alt="Library" />';
snippet[1] = '<img src="http://library.cnu.edu/images/library2.jpg" alt="Library" />';
snippet[2] = '<img src="http://library.cnu.edu/images/library3.jpg" alt="Library" />';
snippet[3] = '<img src="http://library.cnu.edu/images/library4.jpg" alt="Library" />';

randomNumber = Math.floor(Math.random() * snippet.length);

document.write(snippet[randomNumber]);