var imageDir = "images/";

home_off= new Image;
home_off.src = imageDir + "ptr_off.gif";

home_over= new Image;
home_over.src = imageDir + "ptr_over.gif";

concept_off= new Image;
concept_off.src = imageDir + "ptr_off.gif";

concept_over= new Image;
concept_over.src = imageDir + "ptr_over.gif";

book_off= new Image;
book_off.src = imageDir + "ptr_off.gif";

book_over= new Image;
book_over.src = imageDir + "ptr_over.gif";

audiobook_off= new Image;
audiobook_off.src = imageDir + "ptr_off.gif";

audiobook_over= new Image;
audiobook_over.src = imageDir + "ptr_over.gif";

video_off= new Image;
video_off.src = imageDir + "ptr_off.gif";

video_over= new Image;
video_over.src = imageDir + "ptr_over.gif";

seminar_off= new Image;
seminar_off.src = imageDir + "ptr_off.gif";

seminar_over= new Image;
seminar_over.src = imageDir + "ptr_over.gif";

endorsements_off= new Image;
endorsements_off.src = imageDir + "ptr_off.gif";

endorsements_over= new Image;
endorsements_over.src = imageDir + "ptr_over.gif";

film_off= new Image;
film_off.src = imageDir + "ptr_off.gif";

film_over= new Image;
film_over.src = imageDir + "ptr_over.gif";

bylaws_off= new Image;
bylaws_off.src = imageDir + "ptr_off.gif";

bylaws_over= new Image;
bylaws_over.src = imageDir + "ptr_over.gif";

authors_off= new Image;
authors_off.src = imageDir + "ptr_off.gif";

authors_over= new Image;
authors_over.src = imageDir + "ptr_over.gif";

links_off= new Image;
links_off.src = imageDir + "ptr_off.gif";

links_over= new Image;
links_over.src = imageDir + "ptr_over.gif";

function offImage(imageName)
{
  document.images[imageName].src = eval(imageName + "_off" + ".src");
};

function overImage(imageName)
{
  document.images[imageName].src = eval(imageName + "_over" + ".src");
};