pic = new Image();
 pic2 = new Image();
 pic3 = new Image();
 pic4 = new Image();
 pic5 = new Image();
 pic6 = new Image();
 pic7 = new Image();
 pic8 = new Image();
 pic.src = "../img/header_bg_1.jpg";
 pic2.src = "../img/header_bg_2.jpg";
 pic3.src = "../img/header_bg_3.jpg";
 pic4.src = "../img/header_bg_4.jpg";
 pic5.src = "../img/header_bg_5.jpg";
 pic6.src = "../img/header_bg_6.jpg";
 pic7.src = "../img/header_bg_7.jpg";
 pic8.src = "../img/header_bg_8.jpg";