if (document.images) {
        var chicago_on = new Image();
        chicago_on.src = '_img/_global/1_inchicago_H.gif';
        var chicago_off = new Image();
        chicago_off.src = '_img/_global/1_inchicago.gif';
        
        var hsdc_on = new Image();
        hsdc_on.src = '_img/_global/2_company_H.gif';
        var hsdc_off = new Image();
        hsdc_off.src = '_img/_global/2_company.gif';
        
        var hs2_on = new Image();
        hs2_on.src = '_img/_global/3_hs2_H.gif';
        var hs2_off = new Image();
        hs2_off.src = '_img/_global/3_hs2.gif';
        
        var conte_on = new Image();
        conte_on.src = '_img/_global/4_conte_H.gif';
        var conte_off = new Image();
        conte_off.src = '_img/_global/4_conte.gif';
        
        var edcom_on = new Image();
        edcom_on.src = '_img/_global/5_edcom_H.gif';
        var edcom_off = new Image();
        edcom_off.src = '_img/_global/5_edcom.gif';
        
		var scenes_on = new Image();
        scenes_on.src = '_img/_global/6_behindscenes_H.gif';
        var scenes_off = new Image();
        scenes_off.src = '_img/_global/6_behindscenes.gif';
		
	    var spt_on = new Image();
        spt_on.src = '_img/_global/7_support_H.gif';
        var spt_off = new Image();
        spt_off.src = '_img/_global/7_support.gif';
        
        var press_on = new Image();
        press_on.src = '_img/_global/8_press_H.gif';
        var press_off = new Image();
        press_off.src = '_img/_global/8_press.gif';  
        
        var store_on = new Image();
        store_on.src = '_img/_global/9_footnotes_H.gif';
        var store_off = new Image();
        store_off.src = '_img/_global/9_footnotes.gif';  
}        

function On(imgName) {
        if (document.images) {                                  
            document.images[imgName].src = eval(imgName + "_on.src");
        }
}
        
function Off(imgName) {
        if (document.images) {                                  
            document.images[imgName].src = eval(imgName + "_off.src");
        }
}