The soundings are expressed in feet and tenth and refer to the mean low water.
To accompany report of Lt. Col. Geo. L. Gillespie, Corps of Engrs. U.S.A.
"Respectfully forwarded with letter of this date (November 28, 1887) to the Chief of Engineers, Washington, D.C."
1 map ; 28 x 57 cm. on sheet 33 x 61 cm.