The Field Museum Library:
Glaciated bedrock
The Field Museum Library:
Wall section at Chappell
The Field Museum Library:
Excavation of the Chicago Drainage Canal
The Field Museum Library:
Faulted and moved layers of bedrock
The Field Museum Library:
Excavation site of Chicago Drainage Canal
The Field Museum Library:
Excavating Chicago Drainage Canal
The Field Museum Library:
Niagran limestone
The Field Museum Library:
Niagran limestone
The Field Museum Library:
Section of Sanitary and Ship Canal
The Field Museum Library:
Calumet feeder to Drainage Canal
The Field Museum Library:
Sanitary and Ship Canal near Lockport
The Field Museum Library:
Sanitary and Ship Canal near Lockport
The Field Museum Library:
Calumet feeder
The Field Museum Library:
Cliff of Niagran limestone
The Field Museum Library:
Cliff of Niagran limestone
The Field Museum Library:
Spoil banks of Calumet feeder
The Field Museum Library:
Cave in gravel bank