if (document.images) {
image4 = new Image;
image5 = new Image;
image6 = new Image;
image7 = new Image;
image4.src = 'images/skiersmarine/birm01full.jpg';
image5.src = 'images/skiersmarine/birm02full.jpg';
image6.src = 'images/skiersmarine/birm03full.jpg';
image7.src = 'images/skiersmarine/birm04full.jpg';
} else {
image4 = '';
image5 = '';
image6 = '';
image7 = '';
document.rollimg = '';
}