Skip to main content

Thomas Mead and Dr. Hugh S. Bell in front of model of Boulder Dam Cal Tech 1942. Soil conservation tests. Models of check dam. Boulder Dam.

small (250x250 max)
medium (500x500 max)
Large
Extra Large
large ( > 500x500)
Full Resolution
  •  
Loading content ...
you wish to report:


...
Select the collections to add or remove from your search
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
 
OK