NewImg = new Array 
	(
		"images/one.gif",
		"images/two.gif",
		"images/three.gif",
		"images/four.gif",
		"images/five.gif",
		"images/six.gif"
	);
var ImgNum = 0;
var ImgLength = NewImg.length - 1;

var delay = 1500;

var lock = false;
var run;
function chgImg(direction) {
if (document.images) {
ImgNum = ImgNum + direction;
if (ImgNum > ImgLength) {
ImgNum = 0;
}
if (ImgNum < 0) {
ImgNum = ImgLength;
}
document.slideshow.src = NewImg[ImgNum];
   }
}
function auto() {
if (lock == true) {
lock = false;
document.getElementById("play").value=" Play ";
window.clearInterval(run);
}
else if (lock == false) {
lock = true;
document.getElementById("play").value=" Stop ";
run = setInterval("chgImg(1)", delay);
   }
}