Using nivo slider for image slide show, not working

Using nivo slider for image slide show, not working

I test two image and wanted slides show. However it is not working.
  1.  <div id="slider" class="nivoSlider">
        <img src="http://workshop.rs/projects/coin-slider/games/mini_ninjas.jpg"  alt="" />
        <img src="http://workshop.rs/projects/coin-slider/games/prince_of_persia.jpg" alt="" />
    </div>


The demo is at jsfiddle.
Basically it is 2 column layout. The images are put on the left side. Even the simplest one is not working.
  1. $('#slider').nivoSlider();