Subjects
- Iron mining.1
- Laborers.1
- Lifeguards.1
- Lighthouses.1
- Lightships.1
- Loading docks.1
- Lumber industry.1
- Machine shops.1
- Machinery.1
- Manufacturing.1
- Masonry.1
- Metallurgical industry.1
- Metalwork.1
- Mines.1
- Mining.1
- Money.1
- Mountain railroads.1
- Natural Science Building (University of Michigan)1
- Naval yards & naval stations.1
- Office buildings -- Michigan.1