function Layer1()
        {
    eval("document.all.aDiv.style.visibility='hidden'");
       }
  function Layer2(lyr1)
          {
      	 eval("document.all." + lyr1 + ".style.visibility='visible'");
          }

function Layer3()
{
    eval("document.all.bDiv.style.visibility='hidden'");
}

	function Layer4(lyr3)
	{
      	eval("document.all." + lyr3 + ".style.visibility='visible'");
	}

function Layer5()
{
    eval("document.all.cDiv.style.visibility='hidden'");
}

	function Layer6(lyr5)
	{
      	eval("document.all." + lyr5 + ".style.visibility='visible'");
	}