Cannot install

["M. Damerell" <uhah208@sun.rhul.ac.uk>]

Trying to install debian on a sparcstation 2 .  I downloaded
files by binary  ftp  from   ftp.uk.debian.org  
(that is a Unix  ftp command and the  ftp  bin  command)
and checked that they were the same size as the originals.
I got files from

/debian/dists/potato/main/disks-sparc/current/sun4cdm

is this the right location?

First tried floppy.  Got  .../images-1.44/rescue.bin ,
and used rawrite to put it onto a disk.  then tried

boot floppy

The error message says 

cant read disk label

and then something like:

cant use sun disk program (this was some time ago)

Tried:  different disk, different drive, writing disk with
dd  instead of rawrite:  same error. 

Tried to boot netbsd by same method, that worked.

So then I tried to install debian by using tftp. After downloading

tftpboot.img 

from the same directory and putting it onto the tftpd server
I do 

boot net

on the sparc.  This shows a rapidly increasing series of hex 
numbers (I assume this is while the sparc is loading the
boot file), then

TILO
booting linux...

then it jams apparently for ever.
I cannot find anything relevant in TFM. Please any advice?
Thank you, Mark.