For Educators
What are OER?
Find OER
List of OER Courses
Adopted OER
Get Help
Library Resources
For Students
Find Courses
Course Reserves
Impact
About
Map
Map of Philadelphia showing population in year 1920, as enumerated in U.S. Census, and existing electric railway system
Author
: Philadelphia. Department of City Transit
Source
:
Library of Congress - Maps
Collection
:
Cities and Towns
Share
