Force download links to original file

Is it possible to create a link that force your browser to download the original file? Now, the download-link is for example http://images.arnohoogwerf.nl/main.php?cmd=imageorig&var1=Architectuur/AH091201+Woonmagazine+6208.jpg which will open the large jpg in your browser. I'd like to directly save the picture without showing the large image.