A PHP-issue

Hi. I am using the following code to get and display thumbnails from a custom field valued “the_field”. It works fine, but when I have too many of these thumbnails it breaks my design. How do I limit the output from the code below to a certain amount and force the following output on a new line?

<?php $the_field=get_post_meta($post->ID,"the_output",false); ?>

<?php foreach($the_field as $the_output)
{
list($width, $height, $type, $attr) = getimagesize($the_output);
?>
<img src="<?php echo $the_output;?>" <?php echo $attr; ?> alt="">
<?

}?>

Any help would be higly appreciated!