var Pict = new Array(2);
Pict[0] = new Image;
Pict[0].src="title_pic_1.gif";
Pict[1] = new Image;
Pict[1].src="title_pic_2.gif";
var picindex = 1;

var picchangetimeout;

function pict_change()
{
  document.getElementById('picture').src=Pict[picindex].src;
  picindex++;
  if (picindex > 1)
  {  picindex = 0;  }
  picchangetimeout = setTimeout("pict_change()",1500);
}

pict_change();