Serial Number of First Unix System

A post looking at which of the PDP-7 systems at Bell Labs at the time was likely to be the one used by Ken Thompson and Dennis Ritchie.

[Warner Losh] In preparation for a talk on Seventh Edition Unix this fall, I stumbled upon a service list from DEC for all known PDP-7 machines. From that list, and other sources, I believe that PDP-7 serial number 34 was the original Unix machine.