CG> I believe it's a binary archive (.arc is a compression type
  CG> on RISC OS) It contains the boot loader for RPC's.  I
  CG> believe that it may not be up to date as there is a RISC OS
  CG> 4 compatible one around. 
 
I am the person who modified the code to work with RISC OS 4.
I send a copy to Mark Brinicombe months ago so that he could
integrate it into the current distribution, but it seems that
I am the only source of the code. I have email'ed about a dozen
copies to people who have requested it so far.
The modified loader works with earlier versions of RISC OS as well
as 4.0. I think a RISC OS fix is needed for RISC OS 4.03 as it
appears that the SWI that returns the arrangement of the physical
memory in the machine is broken in that version. This can be found
on the Castle Web site (memfix11).
Dave Daniels
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