var whatson_imgs = '<nobr>' + whatson_images.join("") + '</nobr>';
var whatson_pos = 0; 

var Slideshow = Class.create();
	Slideshow.prototype  = {
	initialize: function ()
	{
		this.whatson = $('preview_images');
		this.whatson_txt = $('preview_caption');
		this.whatson_txt.innerHTML = whatson_caption[0];
		this.whatson.innerHTML = whatson_imgs;
	},
	whatson_slideleft: function ()
	{
		if (whatson_pos < whatson_images.length - 1 )
		{
			new Effect.MoveBy(this.whatson, 0, -150,0);
			whatson_pos++;
			this.whatson_txt.innerHTML = whatson_caption[whatson_pos];
		} else {

			whatson_pos = 0;
			backlength = (whatson_images.length * 150) - 150;
			new Effect.MoveBy(this.whatson, 0, backlength);
			this.whatson_txt.innerHTML = whatson_caption[whatson_pos];
		}
	}
};