images = new Array("images/photos/image001.jpg", "images/photos/image002.jpg", "images/photos/image003.jpg", "images/photos/image004.jpg", "images/photos/image005.jpg", "images/photos/image006.jpg", "images/photos/image007.jpg", "images/photos/image008.jpg");

var i = 0;

function nextImage()
{
  i++;
  if (i == 8){
	i = 0;
  }
  filename = images[i];
  document.getElementById("mainimage").src = filename;
}

function prevImage()
{
  i = i-1;
  if (i == -1){
	i = 7;
  }
  filename = images[i];
  document.getElementById("mainimage").src = filename;
}