$('document').ready(function(){
  
  $('.gallery-large').css({'display':'none'});
  $('.gallery-large:first-child').css({'display':'inline'});
  
  $('.gallery-small').css({'cursor':'pointer'});
  
  $('.gallery-small').each(function(i){
    $(this).attr('rel',i+1);
  });
  
  $('.gallery-small').click(function(){
    $('.gallery-large').css({'display':'none'});
    var target = $('.gallery-large:nth-child('+$(this).attr('rel')+')').css({'display':'inline'});
  });
  
});