[Xmca-l] Vygotskian Passage

[Glassman, Michael]

I wonder if somebody might be able to help me.  I seem to remember a passage from Vygotsky where he describes a person going between villages, I think to deliver messages.  He uses some type of external symbol system, maybe tying strings around his finger.  Does anybody know if that really exists and if so where.

Thanks in advance to anybody who might be able to help.

Michael