I found a PDF (page images):

http://www.softwarepreservation.org/projects/LISP/MIT/AIM-00...

The memo was not #1 but #58 (apologies -- my hardcopy is buried someplace, and I made it years ago when rummaging through Marvin's file cabinets for something interesting and ran across it).

But thanks to the miracle of modern science, it's online here: ftp://publications.ai.mit.edu/ai-publications/pdf/AIM-058.pdf

#1 was JMC's memo on Lisp, but (tying back to this thread) you had to manage memory with CONS (malloc()) and erase (free()).

(I note the date was around the time the first PDP-6 was delivered to the AI Lab so the memo was probably timely. Boy, the PFP-10 (basically the 'real version' of the PDP-6) was such a pleasure to write for, with an instruction set that was basically lisp primitives.)

Argh.

http://publications.csail.mit.edu/ai/browse/0000browse.shtml

(It is not there)