function changePicture1(){
			document.getElementById("quadro1").style.display="inline";
			document.getElementById("quadro2").style.display="none";
			setTimeout("changePicture2()",4000);
	}
	
function changePicture2(){
			document.getElementById("quadro2").style.display="inline";
			document.getElementById("quadro1").style.display="none";
			setTimeout("changePicture1()",4000);
}
changePicture1();