function preload(){

normal = new Image();
normal.src = "img/background_start1.jpg";     /* normale-Grafik */
hover = new Image();
hover.src = "img/background_start2.jpg";     /* Highlight-Grafik */


}

function preload_main(){
  
usa_normal = new Image();
usa_normal.src = "../img/usa.gif";
usa_half = new Image();
usa_half.src = "../img/usa_half.gif";

ger_normal = new Image();
ger_normal.src = "../img/deutschland.gif";
ger_half = new Image();
ger_half.src = "../img/deutschland_half.gif";

}

function Wechseln(Bildname,Tauschbildname)
{
document.images[Bildname].src = eval(Tauschbildname + ".src")
}