SpecLisp 1.3 is not based on the original Lisp 1.5 my McCarthy but instead follows the syntax of Stanford Lisp 1.6 (try to find the user manual online by googling "Stanford Lisp 1.6)". If you look around there's a useful summary of the syntax of SpecLisp by Francisco Leon which is called "Review of 'LISP Interpreter'" (actually, I just realised that it's posted here).
SpecLisp is fully featured so you should be able to write some useful Lisp programs with it.
It crashed whilst I was using it on the Fuse 1.5.6 emulator, and so I moved over the ZEsarUX 5.1-SN, which seemed stable.
