if (document.images) {

            img1on = new Image(); 
            img1on.src = "nav/firm_on.jpg";   
            img2on = new Image();
            img2on.src = "nav/design_on.jpg";
            img3on = new Image();
            img3on.src = "nav/portfolio_on.jpg";
            img4on = new Image();
            img4on.src = "nav/publications_on.jpg";
            img5on = new Image();
            img5on.src = "nav/contact_on.jpg";
            img6on = new Image();
            img6on.src = "nav/home_on.jpg";
            img7on = new Image();
            img7on.src = "nav/dowd_on.gif";
            img8on = new Image();
            img8on.src = "nav/ryan_on.gif";
            img9on = new Image();
            img9on.src = "nav/murray_on.gif";
            img10on = new Image();
            img10on.src = "nav/moore_on.gif";
            img11on = new Image();
            img11on.src = "nav/rainey_on.jpg";
            
   
            img1off = new Image(); 
            img1off.src = "nav/firm_off.jpg";   
            img2off = new Image();
            img2off.src = "nav/design_off.jpg";
            img3off = new Image();
            img3off.src = "nav/portfolio_off.jpg";
            img4off = new Image();
            img4off.src = "nav/publications_off.jpg";
            img5off = new Image();
            img5off.src = "nav/contact_off.jpg"; 
            img6off = new Image();
            img6off.src = "nav/home_off.jpg"; 
            img7off = new Image();
            img7off.src = "nav/dowd_off.gif"; 
            img8off = new Image();
            img8off.src = "nav/ryan_off.gif";
            img9off = new Image();
            img9off.src = "nav/murray_off.gif"; 
            img10off = new Image();
            img10off.src = "nav/moore_off.gif";   
            img11off = new Image();
            img11off.src = "nav/rainey_off.jpg";            
       }

function changeIt(imgName,imgSource) {
	  if (document.images) {
            document[imgName].src = eval(imgSource);

        }
}

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

function imgOff(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "off.src");

        }
}