$('next').addEvent('click', function() {
		$clear(start);
		effect();
		$('text').innerHTML = text[whichimage];
		if (!document.images)
		return	
		document.images.slide.src=slideimages[whichimage].src;
		if (whichimage<slideimages.length-1)
		whichimage++;
		else
		whichimage=0;
	});
 
	$('back').addEvent('click', function() {
		$clear(start);
		effect();
		$('text').innerHTML = text[whichimage];
		if (!document.images)
		return	
		document.images.slide.src=slideimages[whichimage].src;
		if (whichimage==0)
		whichimage=slideimages.length-1;
		else
		whichimage--;
	});