function preloadImages(base) {
		   img1_on = new Image;
		   img1_off = new Image;
		   img1_on.src = base + "images/home_on.gif";
		   img1_off.src = base + "images/home.gif";
   		
		   img2_on = new Image;
		   img2_off = new Image;
		   img2_on.src = base + "images/gear_on.gif";
		   img2_off.src = base + "images/gear.gif";
   		
		   img3_on = new Image;
		   img3_off = new Image;
		   img3_on.src = base + "images/rides_on.gif";
		   img3_off.src = base + "images/rides.gif";
   		
		   img4_on = new Image;
		   img4_off = new Image;
		   img4_on.src = base + "images/news_people_on.gif";
		   img4_off.src = base + "images/news_people.gif";
   		
		   img5_on = new Image;
		   img5_off = new Image;
		   img5_on.src = base + "images/training_on.gif";
		   img5_off.src = base + "images/training.gif";
   		
		   img6_on = new Image;
		   img6_off = new Image;
		   img6_on.src = base + "images/fix_it_on.gif";
		   img6_off.src = base + "images/fix_it.gif";
   		
   		
		   img7_on = new Image;
		   img7_off = new Image;
		   img7_on.src = base + "images/tour_de_france_on.gif";
		   img7_off.src = base + "images/tour_de_france.gif";
   		
		   img8_on = new Image;
		   img8_off = new Image;
		   img8_on.src = base + "images/biketown_on.gif";
		   img8_off.src = base + "images/biketown.gif";
   		
		   img9_on = new Image;
		   img9_off = new Image;
		   img9_on.src = base + "images/mountain_bike_on.gif";
		   img9_off.src = base + "images/mountain_bike.gif";
   		
   		
		   img10_on = new Image;
		   img10_off = new Image;
		   img10_on.src = base + "images/events_on.gif";
		   img10_off.src = base + "images/events.gif";
   		
		   img11_on = new Image;
		   img11_off = new Image;
		   img11_on.src = base + "images/discussions_on.gif";
		   img11_off.src = base + "images/discussions.gif";
   		
		   img12_on = new Image;
		   img12_off = new Image;
		   img12_on.src = base + "images/free_newsletter_on.gif";
		   img12_off.src = base + "images/free_newsletter.gif";
   		
		   img13_on = new Image;
		   img13_off = new Image;
		   img13_on.src = base + "images/personal_trainer_on.gif";
		   img13_off.src = base + "images/personal_trainer.gif";
   		
		   img14_on = new Image;
		   img14_off = new Image;
		   img14_on.src = base + "images/shop_on.gif";
		   img14_off.src = base + "images/shop.gif";
   		
		   img15_on = new Image;
		   img15_off = new Image;
		   img15_on.src = base + "images/subscribe_on.gif";
		   img15_off.src = base + "images/subscribe.gif";
		}
		
		function swapImg(imgField,newImg)	{
		
			document[imgField].src = eval(newImg+".src")
			
			}