$(function() {
 var cT = 2000,
  sT = 2000;
 var index = 0,
  $img = $('#slide').children('img'),
  imgLen = $img.length;
 $img.not(':first').css('opacity', '0');
  function start(){ 
  	slides = setInterval(function(){
  	 var next = (index +1) % imgLen;
  	  $img.eq(index).animate({opacity:0},cT); 
  	  $img.eq(next).animate({opacity:1},cT); 
  	  index = next; },sT + cT); 
  }; 
  start();
});