ubuntu@ubuntu:~$ sudo umount /dev/sdb5 ; sudo mount -o ro,uid=999 -t ext4 /dev/sdb5 old_drive
mount: wrong fs type, bad option, bad superblock on /dev/sdb5,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

ubuntu@ubuntu:~$