if (document.images) {            // Active Images
            img1on = new Image();
            img1on.src = "images/linkhome2.gif";
            img2on = new Image();
            img2on.src = "images/linkauthor2.gif";
            img3on = new Image();
            img3on.src = "images/linkread2.gif";
            img4on = new Image();
            img4on.src = "images/linkpurchase2.gif";
            img5on = new Image();
            img5on.src = "images/linkpress2.gif";
            img6on = new Image();
            img6on.src = "images/linkpublications2.gif";

            img1off = new Image();
            img1off.src = "images/linkhome1.gif";
            img2off = new Image();
            img2off.src = "images/linkauthor1.gif";
            img3off = new Image();
            img3off.src = "images/linkread1.gif";
            img4off = new Image();
            img4off.src = "images/linkpurchase1.gif";
            img5off = new Image();
            img5off.src = "images/linkpress1.gif";
            img6off = new Image();
            img6off.src = "images/linkpublications1.gif";


        }

// Function to 'activate' images.
function imgOn(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "on.src");
        }
}

// Function to 'deactivate' images.
function imgOff(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "off.src");
        }
}