var scrollItem = {
	  element: null,
	  originalHeight:0,
	  step:1,
	  top:0,
	 		 	
register: function(item) {
		this.element = item;
		this.orijinalHeight = this.element.getHeight() * -1;
		
	},

run: function() {
		this.top = this.top - this.step;
		if (this.top < this.orijinalHeight) this.top = 130;
		if (this.top > 130) this.top = this.orijinalHeight;
		Element.setStyle(this.element,{top:this.top+'px'});
	},

	up: function () {
		this.step = -4;
	},

	down: function () {
		this.step = 4;
	},
	
	pause: function () {
		this.step = 0;
	},
	
	normal: function () {
		this.step = 1;
	}
	
	};



var ski = Class.create({
  
  initialize: function(element) {
 	this.element = $(element);
 	scrollItem.register(this.element);
	this.start();
},


start: function () {
	new PeriodicalExecuter(this.organize,0.1);
},

	
organize: function () {
	scrollItem.run();
}


});