title: jQuery, get the original height of a div
body: <p>I have some div .frame with a height of 200px.
  When the mouse is over one of these div, with the jQuery function animate(), I'm setting the height of this div to 300px, and when the mouse leaves this div, I'm re-setting its height to 200px.</p>
  
  <p>The script is pretty basic:</p>
  
  <pre><code>$(document).on('mouseenter mouseleave', '.frame', function( e ) {
      var el=$(this);
      if(e.type == "mouseenter"){
          el.stop(true,true).animate({'height':300});
      }else{
          el.stop(true,true).animate({'height':200});
      }  
  });
  </code></pre>
  
  <p>My issue is: from the begining I know that the height of .frame is 200px, but what if I don't know this value? how can set .frame in its original height in the seconde animate()? </p>