jQuery Tools Scrollable keyboard navigation

I'm unable to get the keyboard navigation working on my local install of jQuery Tools S开发者_运维问答crollable.

As you can see, the keyboard can navigate the thumbnails on their demo page, but nothing happens when I press the left or right arrow keys on my page (which has the exact same code as theirs).

Any ideas how I can get the keyboard navigation working?

You only have 5 images on your page, nothing to scroll as its already all visible.

 <!-- 1-5 --> 
  <div> 
     <img src="http://farm1.static.flickr.com/143/321464099_a7cfcb95cf_t.jpg" /> 
     <img src="http://farm4.static.flickr.com/3089/2796719087_c3ee89a730_t.jpg" /> 
     <img src="http://farm1.static.flickr.com/79/244441862_08ec9b6b49_t.jpg" /> 
     <img src="http://farm1.static.flickr.com/28/66523124_b468cf4978_t.jpg" /> 
     <img src="http://farm1.static.flickr.com/164/399223606_b875ddf797_t.jpg" /> 
  </div>