Field fortifications

Sizes

Square
75 X 75
Thumbnail
57 X 90
Small
300 X 469
Medium
700 X 1095
Large
930 X 1455
Extra Large
1500 X 2347

United States. War Dept. Field fortifications. Washington, D.C.. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc96654/. Accessed July 11, 2014.