The Philadelphia Bindery, Inc.

What caught my attention in this book, was the bottom of the back page, where it states:
Wire-O Binding Patents Pending
The Philadelphia Bindery, Inc.
The only information I have been able to find on the Philadelphia Bindery, is a court suit in 1965.
This book, Edward MacHugh's Treasury of Gospel Hymns and Poems was copyrighted in 1938 and published by
The Rodeheaver, Hall-Mack Company.
Spiral binding started by the Spiral Binding Co. started in 1932 and was the first mechanical binding company in the U.S.A.
Still searching for wire-o binding patent & Philadelphia Bindery history.
Dave