var aryImages = new Array();

aryImages[0] = "../../images/button_prescribes_medication_ro.jpg";
aryImages[1] = "../../images/button_lookupdrugs_ro.jpg";
aryImages[2] = "../../images/button_RXindex_ro.jpg";
aryImages[3] = "../../images/button_Humanaprescriptiontools_ro.jpg";
aryImages[4] = "../../images/button_drugsandtreatments_ro.jpg";

for (i=0; i < aryImages.length; i++) 
{
    var preload = new Image();
    preload.src = aryImages[i];
}