function showLayer(layer)
{
	if(layer > -1)
	{
		//alert("LAYER " + layer);
		for(i=1; i<=14; i++)
		{
			document.getElementById(i).style.display = "none";
		}
			document.getElementById((layer+1)).style.display = "block";
	}
	else
	{
		for(i=1; i<=14; i++)
		{
			document.getElementById(i).style.display = "none";
		}
	}
}