Yes, gnu emacs runs on 4D's

Tue Sep 19 06:53:40 AEST 1989

   Date: 15 Sep 89 15:15:19 GMT
   From: Gary Klaassen <jarvis.csri.toronto.edu!utgpu!utzoo!yunexus!gklaass at rutgers.edu>

   I have been told that getting GNU Emacs running on an SG 4D box is
   a big job.  

This is not true.  The 4D is fully supported in recent releases.

The latest version (18.55) is from many places including
prep.ai.mit.edu in the directory /u2/emacs. 

- Eric