var CURRENT = 1
    function set_current( i ) {
        CURRENT = i
    }
    function thumb( number ) {
        if( document.getElementById ) {
            if( CURRENT == number ) return false;

            var current_image = document.getElementById( "image" + CURRENT )
            var current_thumb = document.getElementById( "thumb" + CURRENT )
            var new_image = document.getElementById( "image"+ number )
            var new_thumb = document.getElementById( "thumb"+ number )

            current_image.style.display = "none";
            current_thumb.className = ""
            new_image.style.display = "block"
            new_thumb.className = "active"

            set_current( number )
        }
        return false;
    }