remove an .append() to return the class to it's orgian state

remove an .append() to return the class to it's orgian state

I'm loading up a ul for a image slider but I need to remove the images
(ul) when the slider is closed because I will later need to reload the ul
for another set of different images.
here is how I'm loading the slider.
var get_images = [ "show_1.jpg", "show_2.jpg", "show_3.jpg", "show_4.jpg"];
$.each(get_images, function(i,img){
$('#container ul').append('<li><a href="#" class="thumbnail"><img
src="'+img+'"/></a></li>');
});