function PreloadImages(length, path, type) {
                        for(var i = 1; i<=length; i++) {
                            this[i]= new Image()
                            this[i].src= path + i + type
                        }
                        return this
                    }

                    over=new PreloadImages(11,'../img/over','.gif')
                    norm=new PreloadImages(11,'../img/norm','.gif')

                    function rollOn(num){
                    if(document.images)
                        eval('document.images["norm'+num+'"].src='+'over[num].src')
                    }
                    function rolloff(num){
                    if(document.images)
                        eval('document.images["norm'+num+'"].src='
                                +'norm[num].src')
                    }