Event.observe(window, 'load', loadAccordions, false);

function loadAccordions() {
			var topAccordion = new accordion('horizontal_container', {
				classNames : {
					toggle : 'horizontal_accordion_toggle',
					toggleActive : 'horizontal_accordion_toggle_active',
					content : 'horizontal_accordion_content'
				},
				defaultSize : {
					width : 570 
				},
				direction : 'horizontal'
			});
			
		
			// Open second one
			topAccordion.activate($$('#horizontal_container .horizontal_accordion_toggle')[0]);
}