if (document.images){
		picone = new Image(100,100); picone.src = "images/garden_wall.jpg";
		pictwo = new Image(100,100); pictwo.src = "images/garden_wall2.jpg";
		picthree = new Image(100,100); picthree.src = "images/wall_and_corner1.jpg";
		picfour = new Image(100,100); picfour.src = "images/wall_and_corner2.jpg";
		picfive = new Image(100,100); picfive.src = "images/wall_on_slope1.jpg";
		picsix = new Image(100,100); picsix.src = "images/wall_on_slope2.jpg";
		}

function swap(imageName, imageFile) {if(!document.images) return;
eval('document.images[imageName].src = '+imageFile +'.src');}