//defer the instantiation of Lightbox. Call when the page has finished loading.
init = function(){
   //creating a data source object
  var dataSource = {
	 	photo1:{url:"day1/images/IMG_0923.jpg"},
	 	photo2:{url:"day1/images/IMG_0959.jpg"},
	 	photo3:{url:"day1/images/IMG_1008.jpg"},
	 	photo4:{url:"day1/images/IMG_1067.jpg"},
	 	photo5:{url:"day1/images/IMG_1083.jpg"},
		photo6:{url:"day1/images/IMG_1115.jpg"},
		photo7:{url:"day1/images/IMG_1121.jpg"},
		photo8:{url:"day1/images/IMG_1134.jpg"},
		photo9:{url:"day1/images/IMG_1167.jpg"},
		photo10:{url:"day1/images/IMG_1211.jpg"},
		photo11:{url:"day1/images/IMG_1218.jpg"},
		photo12:{url:"day1/images/IMG_1225.jpg"},
		photo13:{url:"day1/images/IMG_1251.jpg"},
		photo14:{url:"day1/images/IMG_1327.jpg"},
		photo15:{url:"day1/images/IMG_1353.jpg"},
		photo16:{url:"day1/images/IMG_1374.jpg"},
		photo17:{url:"day1/images/IMG_1378.jpg"},
		photo18:{url:"day1/images/IMG_1384.jpg"},
		photo19:{url:"day1/images/IMG_1386.jpg"},
		photo20:{url:"day1/images/IMG_1435.jpg"},
		photo21:{url:"day1/images/IMG_1471.jpg"},
		photo22:{url:"day1/images/IMG_1500.jpg"},
		photo23:{url:"day1/images/IMG_1502.jpg"},
		photo24:{url:"day1/images/IMG_1524.jpg"},
		photo25:{url:"day1/images/IMG_1558.jpg"},
		photo26:{url:"day1/images/IMG_1651.jpg"},
		photo27:{url:"day1/images/IMG_1666.jpg"},
		photo28:{url:"day1/images/IMG_1673.jpg"},
		photo29:{url:"day1/images/IMG_1675.jpg"},
		photo30:{url:"day1/images/IMG_1699.jpg"},
		photo31:{url:"day1/images/IMG_1730.jpg"},
		photo32:{url:"day1/images/IMG_1845.jpg"},
		photo33:{url:"day1/images/IMG_1882.jpg"},
		photo34:{url:"day2/images/IMG_2176.jpg"},
		photo35:{url:"day2/images/IMG_2178.jpg"},
		photo36:{url:"day2/images/IMG_2301.jpg"},
		photo37:{url:"day2/images/IMG_2329.jpg"},
		photo38:{url:"day2/images/IMG_2343.jpg"},
		photo39:{url:"day2/images/IMG_2401.jpg"},
		photo40:{url:"day2/images/IMG_2499.jpg"},
		photo41:{url:"day2/images/IMG_2582.jpg"},
		photo42:{url:"day2/images/IMG_2607.jpg"},
		photo43:{url:"day2/images/IMG_2647.jpg"},
		photo44:{url:"day2/images/IMG_2656.jpg"},
		photo45:{url:"day2/images/IMG_2706.jpg"},
		photo46:{url:"day2/images/IMG_2778.jpg"},
		photo47:{url:"day2/images/IMG_2841.jpg"},
		photo48:{url:"day2/images/IMG_2843.jpg"},
		photo49:{url:"day2/images/IMG_2844.jpg"},
		photo50:{url:"day2/images/IMG_2846.jpg"},
		photo51:{url:"day2/images/IMG_2849.jpg"},
		photo52:{url:"day2/images/IMG_2851.jpg"},
		photo53:{url:"day2/images/IMG_2854.jpg"},
		photo54:{url:"day2/images/IMG_2871.jpg"},
		photo55:{url:"day2/images/IMG_2883.jpg"},
		photo56:{url:"day2/images/IMG_2884.jpg"},
		photo57:{url:"day2/images/IMG_2885.jpg"},
		photo58:{url:"day2/images/IMG_2907.jpg"},
		photo59:{url:"day2/images/IMG_2922.jpg"},
		photo60:{url:"day2/images/IMG_2954.jpg"},
		photo61:{url:"day2/images/IMG_2966.jpg"},
		photo62:{url:"day2/images/IMG_2983.jpg"},
		photo63:{url:"day2/images/IMG_2984.jpg"},
		photo64:{url:"day2/images/IMG_2985.jpg"},
		photo65:{url:"day2/images/IMG_3027.jpg"},
		photo66:{url:"day2/images/IMG_3032.jpg"},
		photo67:{url:"day2/images/IMG_3037.jpg"},
		photo68:{url:"day2/images/IMG_3058.jpg"},
		photo69:{url:"day2/images/IMG_3065.jpg"}
		  };

  //Instantiate a Lightbox object
  var lightbox = new YAHOO.com.thecodecentral.Lightbox({
    imageBase:'http://wwwdev.wharton.upenn.edu/alumni/inc/gallery/lightbox', 
    dataSource: dataSource
  });
}
YAHOO.util.Event.on(window, 'load', init);