AA
| Ann Arbor | 5 |
ACL
| Atlantic Coast Line | 1 |
ATSF
| Atchison Topeka & Santa Fe | 1 |
CGW
| Chicago Great Western | 6 |
DMIR
| Duluth Missabe & Iron Range | 1 |
GMO
| Gulf Mobile & Ohio | 1 |
GN
| Great Northern | 1 |
HWCX
| Halliburton Company | 1 |
LN
| Louisville & Nashville | 2 |
MI
| Missouri & Illinois | 1 |
MON
| Monon Route | 3 |
NYC
| New York Central | 1 |
PRR
| Pennsylvania Railroad | 2 |
SI
| Union Pacific Railroad Company (Spokane International) | 1 |
SLSF
| Saint Louis-San Francisco | 1 |
UP
| Union Pacific Railroad Company | 1 |