function clip() {
 	
	var contWidth = 244;		// larghezza del contenitore
	var contHeight = 600;	// altezza del contenitore
	var id1 = document.getElementById('slideA');
	var id2 = document.getElementById('slideB');
	var height = id1.offsetHeight;
	id1.style.top = parseInt(id1.style.top)-1 + 'px';
	document.getElementById('slideCont').style.height = contHeight + "px";
	document.getElementById('slideCont').style.clip = 'rect(auto,'+ contWidth +'px,' + contHeight +'px,auto)';
	id2.style.display = '';
	if(parseFloat(id1.style.top) == -(height/2)) {
 id1.style.top = '0px';
 }
	setTimeout(clip,30)
	        
}


addLoadEvent
function addLoadEvent(func) {
	var oldonload = window.onload;
	if (typeof window.onload != 'function') {
 window.onload = func;
 }
	else {
 window.onload = function() {		if (oldonload) {
 oldonload();
 }
		func();
				    }
	          }
				    }



addLoadEvent(function() {
  clip();
});