function loadImages(){
  var img1 = new Image(); img1.src = "images/gallery/battery_cage_shed.jpg";
  var img2 = new Image(); img2.src = "images/gallery/battery_cage_hens1.jpg";
  var img3 = new Image(); img3.src = "images/gallery/battery_cage_hens2.jpg";
  var img4 = new Image(); img4.src = "images/gallery/battery_cage_hen_infection.jpg";
  var img5 = new Image(); img5.src = "images/gallery/battery_cage_hen_trapped.jpg";
  var img6 = new Image(); img6.src = "images/gallery/battery_cage_hen_featherpecked.jpg";
  var img7 = new Image(); img7.src = "images/gallery/battery_cage_chick_beaktrimmed.jpg";
  var img8 = new Image(); img8.src = "images/gallery/battery_cage_hens_beakstrimmed.jpg";
  var img9 = new Image(); img9.src = "images/gallery/battery_cage_chicks_discarded.jpg";
  var img10 = new Image(); img10.src = "images/gallery/battery_cage_shed2.jpg";
  var img11 = new Image(); img11.src = "images/gallery/battery_cage_hen_rescued.jpg";
}

function roll_over(){
   var imgsrc = $(this).attr('src');
   var matches = imgsrc.match('_on');
	 if (!matches) {
	   imgsrcON = imgsrc.replace(/.jpg$/ig,"_on.jpg");
		 $(this).attr("src", imgsrcON);
	 }
}

function roll_out(){
   var imgsrc = $(this).attr('src');
	 imgsrcOFF = imgsrc.replace(/_on.jpg$/ig,".jpg");
	 $(this).attr("src", imgsrcOFF);
}

$(document).ready(function(){
	 
   //gallery
	 $('#gallery > tbody > tr > td > img').mouseup(function(event){
	   var thmSrc = $(this).attr('src');
		 var caption = $(this).attr('alt');
		 fullSrc = thmSrc.replace(/-.jpg$/ig,".jpg");
		 $("#viewer").attr("src",fullSrc);	
		 
		 $("#caption").text(caption);
		 
	 });
   
});