var DURATION = 0.5;  /* Number of seconds taken for transition */
var BORDER_OFFSET = 12; /* Offset to width of thumbnail from border or margin values */

function scrollPhotos(distance) {
	
	var list = document.getElementById('photoList');
	var elements = list.getElementsByTagName('li');
	
	var totalHeight = 0;
	
	for (i=0; i<elements.length; i++) {
		totalHeight += (elements[i].offsetHeight + BORDER_OFFSET)/3;
	}
		
	new Slider('thumbnailsSlider','thumbnailsViewport', 0, distance, DURATION, -1, totalHeight);
}