[ale] how to mount an initrd file?

[christopher at bergeron.com (Christopher Bergeron)]

I thought this was a straightforward task, but I'm having trouble 
mounting an initrd.img file.  When I try:

mount -o loop initrd.img directory_to_mount_to

I'm getting a "must specify filesystem" error.  Does anyone have any 
idea on what I'm doing wrong?  Can I not mount this initrd.img file or 
am I in fact, not specifying the correct filesystem?  I've tried -t 
ext2  and -t ext3 (and -t tmpfs and -t cramfs), but to no adeu.

Does anyone have any ideas?

Thanks in advance,
CB