// Netscape 3.0 compatibility test (for javascript image swapping)
	compat = false;
	if( parseInt( navigator.appVersion ) >= 3 ) {
		compat = true; 
	}

// cache images for quick swapping
	if( compat ) {

		lo_request = new Image();
		lo_request.src = "img/lo_request.gif";
		l_request = new Image();
		l_request.src = "img/l_request.gif";
		
		lo_reading = new Image();
		lo_reading.src = "img/lo_reading.gif";
		l_reading = new Image();
		l_reading.src = "img/l_reading.gif";
		
		lo_resources = new Image();
		lo_resources.src = "img/lo_resources.gif";
		l_resources = new Image();
		l_resources.src = "img/l_resources.gif";
		
		
		
		
		
	}
	

// swap images using the cached images

function changeImg(x, y) {
	if( compat ) {
		document.images[x].src=eval(y+'.src'); 
		}
	}