if (document.images) {
  image1 = new Image;
  image2 = new Image;
  image3 = new Image;
  image4 = new Image;
  image5 = new Image;
  image6 = new Image;
  image7 = new Image;
  image8 = new Image;
  image9 = new Image;
  image10 = new Image;
  image11 = new Image;
  image12 = new Image;
  image13 = new Image;
  image14 = new Image;
  image15 = new Image;
  image16 = new Image;
  image17 = new Image;
  image18 = new Image;
  image19 = new Image;
  image20 = new Image;
  image1.src = 'images/port01.jpg';
  image2.src = 'images/port02.jpg';
  image3.src = 'images/port03.jpg';
  image4.src = 'images/port04.jpg';
  image5.src = 'images/port05.jpg';
  image6.src = 'images/port06.jpg';
  image7.src = 'images/port07.jpg';
  image8.src = 'images/port08.jpg';
  image9.src = 'images/port09.jpg';
  image10.src = 'images/port10.jpg';
  image11.src = 'images/port11.jpg';
  image12.src = 'images/port12.jpg';
  image13.src = 'images/port13.jpg';
  image14.src = 'images/port14.jpg';
  image15.src = 'images/port15.jpg';
  image16.src = 'images/port16.jpg';
  image17.src = 'images/port17.jpg';
  image18.src = 'images/port18.jpg';
  image19.src = 'images/port19.jpg';
  image20.src = 'images/port20.jpg';
  
} else {
  image1 = '';
  image2 = '';
  image3 = '';
  image4 = '';
  image3 = '';
  image5 = '';
  image6 = '';
  image7 = '';
  image8 = '';
  image9 = '';
  image10 = '';
  image11 = '';
  image12 = '';
  image13 = '';
  image14 = '';
  image15 = '';
  image16 = '';
  image17 = '';
  image18 = '';
  image19 = '';
  image20 = '';
  
  document.rollimg = '';
}