// test the browser to make sure it's ok
var browserName = navigator.appName;
var browserVer = parseInt(navigator.appVersion);
var browserOK = (((browserName == "Netscape") && (browserVer >= 3)) || 
  ((browserName == "Microsoft Internet Explorer") && (browserVer >= 4)));

// URLs of images in slide show

var totalPic = 53;   //this is the number to be channged
var slideURL = new Array(53)
// create slide URL
for (x=1;x<=totalPic;x++){
    slideURL[x-1]= x + ".jpg";
}

// delay between slides (in milliseconds)
var slideDelay = 10000;
// Index of the current slide
var curSlide = 0;
// timeout id for the current setTimeout command
var curTimeout;

function showSlide() {
  if (browserOK) {
    // alert(slideURL.length);
    curSlide = ((curSlide + 1) % slideURL.length);
    // alert(curSlide);
    document.images["slideImg"].src = "pho1/" + slideURL[curSlide];
    curTimeout = setTimeout("showSlide()", slideDelay);
  } else {
    // show an error message for older browsers
    alert("This page requires Netscape 3.0+ or IE 4.0+");
  }
}

function goNext() {
  if (browserOK) {
    clearTimeout(curTimeout);
    showSlide();
  }
}

function goPrev() {
  if (browserOK) {
    clearTimeout(curTimeout);
    curSlide = (((curSlide - 2) + slideURL.length) % slideURL.length);
    showSlide();
  }
}