The whaleback was a unique esign of a vessel built for carrying bulk cargo by water. The term was never an official designation, but developed in common usage in response to the design's appearance when vessels were fully loaded. A total of 43 such vessels were constructed from 1887 to 1898. All but two were built initially as lake freighters for service on the Great Lakes of Canada and the United States. Six were built at Duluth, Minnesota; thirty-three were built at West Superior, Wisconsin; two at Brooklyn, New York; one at Everett, Washington; and one (without the designer’s approval) at Sunderland, England. A number of the Great Lakes vessels left the lakes for service on salt water seas.