from survey made between March 29th & April 9th 1856 under the direction of Brevet Lieut. Col. J.D. Graham, Major U.S. Top. Engineers. Superintending Engineer of Lake Michigan Works
from survey made between 10th & 15th of Sepbr. 1856 under the direction of Brevet Lieut. Col. J.D. Graham, Major U.S. Top. Engineers. Superintending Engineer of Lake Michigan Works