var oct15_off = new Image();
var oct16_off = new Image();
var oct17_off = new Image();

var oct15_on = new Image();
var oct16_on = new Image();
var oct17_on = new Image();


oct15_off.src = "./images/oct15.gif";
oct16_off.src = "./images/oct16.gif";
oct17_off.src = "./images/oct17.gif";

oct15_on.src = "./images/oct15-over.gif";
oct16_on.src = "./images/oct16-over.gif";
oct17_on.src = "./images/oct17-over.gif";