1940
U.S. Dept. of Agriculture Bureau of Soils
1:63k
1878
Snyder, Van Vechten & Co.
1:253k
1911
1:120k
1910
1:120k
1981
1:100k
1972
U.S. Lake Survey
1:80k
1969
U.S. Lake Survey
1:80k
1966
U.S. Lake Survey
1:80k
1964
U.S. Lake Survey
1:80k
1935
U.S. Lake Survey
1:15k