"The POLYPHASE Slide Rule"
by: William E. Breckenridge
Copyright 1924
This is a short preview of the manual for identification purposes. Complete scans will be provided when time is available. If someone has a particular need to view the entire version of this manual, please email me and I will put it first in my list to finish. Email address
This manual is from the collection of Clark McCoy
The scans of this manual were provided by Clark McCoy
These web pages were produced by Clark McCoy