Railroad Archives Online
- CollectionD0027 - Timothy Miller Collection
- Series004 - Northern Pacific Railroad Company
- Subseries Level 1009 - Engineering Records
- Subseries Level 2008 - Physical plant drawing
- Subseries Level 3001 - Bridges
- 2519 more...
- ItemBB017003 - Northern Pacific Engineering Drawing: General Plan, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017004 - Northern Pacific Engineering Drawing: Through Plate Girder Span, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017005 - Northern Pacific Engineering Drawing: Through Plate Girder Span, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017006 - Northern Pacific Engineering Drawing: Through Plate Girder Span, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017007 - Northern Pacific Engineering Drawing: Detail Floor Beam/Stringers, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017008 - Northern Pacific Engineering Drawing: Detail of Bearings, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017009 - Northern Pacific Engineering Drawing: Shop Plan - Plate Girder Span, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017010 - Northern Pacific Engineering Drawing: Shop Plan - Girders, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- ItemBB017011 - Northern Pacific Engineering Drawing: Shop Plan - E and F Stringers, Bridge 87 (139) - Hell Gate River, West of Bearmouth, Montana, undated
- 5200 more...