var imageFiles_4h_15 = new Array();
imageFiles_4h_15['0'] = new Array ('_images/4h_Freezing_Conditions.gif', '_images/4h_Freezing_ConditionsMouseover.gif');

function image_on_4h_15 (position) {
   var doc = eval("document.image4h_15" + position);
   doc.src = imageFiles_4h_15[position][1];
}

function image_off_4h_15 (position) {
   var doc = eval("document.image4h_15" + position);
   doc.src = imageFiles_4h_15[position][0];
}