function Bildan1 () {
  if (document.getElementById)
    document.getElementById("Bildlupe1").style.visibility = "visible";
}
function Bildaus1 () {
  if (document.getElementById)
    document.getElementById("Bildlupe1").style.visibility = "hidden";
}
function Bildan2 () {
  if (document.getElementById)
    document.getElementById("Bildlupe2").style.visibility = "visible";
}
function Bildaus2 () {
  if (document.getElementById)
    document.getElementById("Bildlupe2").style.visibility = "hidden";
}
function Bildan3 () {
  if (document.getElementById)
    document.getElementById("Bildlupe3").style.visibility = "visible";
}
function Bildaus3 () {
  if (document.getElementById)
    document.getElementById("Bildlupe3").style.visibility = "hidden";
}
function Bildan4 () {
  if (document.getElementById)
    document.getElementById("Bildlupe4").style.visibility = "visible";
}
function Bildaus4 () {
  if (document.getElementById)
    document.getElementById("Bildlupe4").style.visibility = "hidden";
}